Part 16

_Primates_ are an order of Monodelphia or Placentalia, including lemurs, monkeys, and man. They are nearly all adapted to an arboreal life. The hand (manus) and the foot (pes) nearly always have five digits provided with flat nails. The pectoral and pelvic limbs are prehensile, owing to the fact that the thumb (pollex) and big toe (hallux) are more or less completely opposable to the other digits. The orbital fossa is completely surrounded by a bony rim. The femur does not have a third trochanter. The internal condyle of the humerus does not have a foramen above it. The clavicles are always well developed. The testes descend into a scrotum. On the thoracic region there are nearly always two teats. The placenta may be non-deciduate, or deciduate and metadiscoidal.

The order of Primates is subdivided into the following sub-orders, viz.:

Sub-order 1.—_Lemuroidea._ Sub-order 2.—_Anthropoidea._

_Lemuroidea._ The Lemurs are small, monkey-like quadrupeds. They are mostly nocturnal, arboreal creatures of comparatively low organization. The body is furry. The orbital and temporal fossæ freely communicate. The lachrymal foramen is situated outside the orbital fossa. The dentition of the Lemurs varies greatly; in some of them it is 2/2 1/1 3/3 3/3 for both jaws. In nearly all of them the median incisors of the upper jaw are separated by a median space. Both feet have flat nails on all the digits, except the second of the hind-foot, which has a claw. The thumb (pollex) and the big toe (hallux) are well developed. The cerebral hemispheres are only slightly convoluted, and do not entirely overlap the cerebellum. The transverse colon is almost always folded on itself. There may be a pair of teats on the abdomen. The uterus is two-horned, and the placenta is diffuse.

This sub-order comprises the Lemurs proper (_Tarsius_, _Lemur_, and other genera) and the Aye-Ayes (_Chiromys_).

_Anthropoidea._ The Anthropoidea are the most highly organized Primates. They are chiefly modified for an arboreal life. The body is hairy instead of furry, but only slightly so in man. The incisors do not exceed 2/2; the molars are 3/3, except in the marmosets, where they are 2/2. The upper, median incisors are in close contact. The orbital and temporal fossæ are separated by a broad vertical plate. The lachrymal foramen is situated inside the orbital fossa. All of the digits are provided with flat nails, except in the Hapalidæ, in which all except the big toe (hallux) are provided with a claw. In some the thumb (pollex) is rudimentary or absent. The clavicle is well developed. The cerebrum is usually richly convoluted, and more or less completely covers the cerebellum. The uterus has no horns. The placenta is deciduate and metadiscoidal.

The Anthropoidea are subdivided into the two following groups:

Super-family 1.—_Platyrrhinæ_ (New-World Monkeys). Super-family 2.—_Catarrhinæ_ (Old-World Monkeys).

The Platyrrhinæ or New-World Monkeys are subdivided into the following families, viz.:

Family 1.—_Hapalidæ._ Family 2.—_Cebidæ._

The Catarrhinæ or Old-World Monkeys are subdivided into the following families, viz.:

Family 1.—_Cercopithecidæ._ Family 2.—_Simiidæ._ Family 3.—_Hominidæ._

_Hapalidæ._ The Hapalidæ or Marmosets are no larger than squirrels, being the smallest monkeys. They are found mostly in Brazil.

There is a broad septum between the nostrils. Their dentition is 2/2 1/1 3/3 2/2, and is distinctive, for the remaining Anthropoidea have 3/3 molars. The tail is long, hairy, and non-prehensile. The arms are not longer than the legs. The thumb (pollex) is long, but is not opposable. All the digits except the great toe (hallux), which is small, have curved, pointed claws. There is no bony external auditory meatus. There are no cheek pouches, or ischial callosities. The Hapalidæ often bear three young ones at a birth, whereas the other Anthropoidea commonly bear but one. There are two genera of Marmosets, viz.: _Midas_ and _Hapale_.

_Cebidæ._ The Cebidæ are most at home in Brazil. They have a broad septum between the nostrils. Many of them have prehensile tails. The dental formula is 2/2 1/1 3/3 3/3, and is characteristic. There is no bony external auditory meatus. There are no cheek pouches, or ischial callosities. All the digits are provided with flat nails. The thumb (pollex) is not opposable.

This family includes the following genera, viz.: Tee Tees (_Callithrix_), Howling Monkeys (_Mycetes_), Spider Monkeys (_Ateles_), Squirrel Monkeys (_Chrysothrix_), and Capuchin Monkeys (_Cebus_).

_Cercopithecidæ._ This family includes the Old-World dog-like Apes. They are quadrupeds, and the muzzle or snout is quite dog-like. There is a narrow septum between the nostrils. The dental formula is 2/2 1/1 2/2 3/3. The sternum is narrow. The tail is not prehensile. The cæcum has no appendix vermiformis. There is a bony external auditory meatus. There may or may not be cheek pouches. Over the rough surface of the everted ischia the skin forms callosities (ischial callosities) which are often brightly colored. The thumb (pollex), when present, is opposable. This family includes two genera, Macaques (_Macacus_) and Baboons (_Cynocephalus_).

_Simiidæ._ This family includes the Anthropoid Apes of the Old World. They are less quadrupeds than the former, often walking in a semi-erect position. The dental formula is 2/2 1/1 2/2 3/3. The sternum is broad. The cæcum has an appendix vermiformis. The nasal septum is narrow. The pectoral limbs are much longer than the pelvic ones. There is a bony external auditory meatus. There are no cheek pouches. Only in the Gibbons are there ischial callosities, in whom they are small. The thumb (pollex) is opposable. No visible tail. This family includes the following genera, viz.: Chimpanzees (_Anthropopithecus_), Gorillas (_Gorilla_), Orangs (_Simia_), and the Gibbons (_Hylobates_).

_Hominidæ._ This family of Anthropoidea includes only the human species (_Homo sapiens_). The dental formula is 2/2 1/1 2/2 3/3. The tail is not visible. The Hominidæ differ from the Simiidæ, structurally, mainly in the more perfect assumption of the erect attitude. There is a more complete adaptation of the pelvic limbs to bearing the weight of the body, correlated with compensating alteration in the curvature of the spinal column. The big toe (hallux) is not opposable, and also it is often longer, never shorter than the other toes, and is not abducted from them. He has a far better heel than the Simiidæ. The thumb is far more opposable in man. There is a greater length of the pelvic limbs compared with the pectoral limbs. The canine teeth are much smaller and do not project beyond the level of the others. The brain has a much greater size and complexity. Man has a larger forehead, smaller cheek bones, smaller supraorbital ridges, a less protrusive face, and a true, well-marked chin.

The Simiidæ are subdivided into the two following groups, viz.:

Sub-family 1.—_Hylobatinæ._ Genus 1.—_Hylobates_ (Gibbons). Sub-family 2.—_Simiinæ._ Genus 1.—_Simia_ (Orangs). Genus 2.—_Gorilla_ (Gorillas). Genus 3.—_Anthropopithecus_ (Chimpanzees).

SYNOPSIS OF THE PLANT KINGDOM.

GROUP A. PROTOPHYTA.

GROUP B. METAPHYTA.

The Metaphyta are subdivided into:

1. _Cryptogams_: Flowerless plants. 2. _Phanerogams_: Flowering plants.

The Cryptogams are subdivided into:

1. _Thallophyta_: Seaweeds, Fungi, Lichens. 2. _Bryophyta_: Mosses, Liverworts. 3. _Pteridophyta_: Ferns, Horsetails, Clubmosses.

The Phanerogams are subdivided into:

1. _Gymnospermæ_:

Order a.—_Cycadaceæ_: Cycads. Order b.—_Coniferæ_: Pines, Spruces, Cypresses.

2. _Angiospermæ_:

Class 1.—_Monocotyledones_: Grasses, Palms. Class 2.—_Dicotyledones_: Oaks, Poplars, Elms.

SECTION VIII.

WORKS OF REFERENCE.

WORKS OF REFERENCE.

The following books have been the constant companions of the author during the preparation of his “First Book in Organic Evolution”:—

GRANT ALLEN, The Colours of Flowers. A. C. ABBOT, Principles of Bacteriology. FRANK BAKER, The Ascent of Man. THOMAS BELT, Naturalist in Nicaragua. H. W. BATES, Naturalist of the Amazons. F. E. BEDDARD, Animal Coloration. A. H. BRADFORD, Heredity and Christian Problems. F. M. BALFOUR, A Treatise on Comparative Embryology. D. G. BRINTON, Races and Peoples. P. C. BURT, A History of Modern Philosophy. PAUL CARUS, The Soul of Man. PAUL CARUS, The Ethical Problem. PAUL CARUS, The Idea of God. PAUL CARUS, Homilies of Science. PAUL CARUS, Fundamental Problems. ARTHUR CLARKSON, A Text-Book of Histology. EDWARD CLODD, The Story of Creation. EDWARD CLODD, The Story of Primitive Man. EDWARD CLODD, A Primer of Evolution. CARPENTER-DALLINGER, The Microscope and its Revelations. A. DE QUATREFAGES, The Natural History of Man. E. D. COPE, The Primary Factors of Organic Evolution. CHARLES DARWIN, The Origin of Species. CHARLES DARWIN, The Descent of Man. CHARLES DARWIN, Animals and Plants under Domestication. J. D. DANA, New Text-Book of Geology. BASHFORD DEAN, Fishes, Living and Fossil. J. W. DRAPER, History of the Intellectual Development of Europe. J. W. DRAPER, Conflict between Religion and Science. H. H. DONALDSON, The Growth of the Brain. R. L. DUGDALE, The Jukes. HENRY DRUMMOND, The Ascent of Man. HAVELOCK ELLIS, Man and Woman. HAVELOCK ELLIS, The Criminal. JOHN FISKE, The Unseen World. JOHN FISKE, The Idea of God. JOHN FISKE, The Destiny of Man. JOHN FISKE, Excursions of an Evolutionist. JOHN FISKE, Myths and Myth-Makers. ENRICO FERRI, Criminal Sociology. SIR W. H. FLOWER, Osteology of the Mammalia. FUNK and WAGNALL, Standard Dictionary of the English Language. THEODORE GILL, The Families of Fishes. THEODORE GILL, Articles on Fishes in the Riverside Natural History. JOHN C. GALTON, Ecker’s The Human Brain. FRANCIS GALTON, Hereditary Genius. FRANCIS GALTON, Natural Inheritance. FRANCIS GALTON, English Men of Science, their Nature and Nurture. C. GEGENBAUR, Elements of Comparative Anatomy. J. M. GUYAU, Education and Heredity. GEDDES and THOMSON, The Evolution of Sex. HARPER’S Latin Dictionary. T. H. HUXLEY, Anatomy of Vertebrated Animals. T. H. HUXLEY, Man’s Place in Nature. T. H. HUXLEY, Origin of Species. T. H. HUXLEY and MARTIN, Practical Biology. T. H. HUXLEY, Science and Culture, and other Essays. HERTWIG-MARK, Text-Book of Embryology. DAVID J. HILL, Genetic Philosophy. HERTWIG-CAMPBELL, The Cell. ROBERT HARTMAN, The Anthropoid Apes. GEORGE HASLAM, Ecker’s Anatomy of the Frog. REV. W. HOUGHTON, Sketches of British Insects. E. KLEIN, Micro-organisms and Disease. G. T. LADD, Outlines of Physiological Psychology. CESARE LOMBROSO, The Man of Genius. SIR JOHN LUBBOCK, The Beauties of Nature. SIR JOHN LUBBOCK, Ants, Bees, and Wasps. ARNOLD LANG, Text-Book of Comparative Anatomy. JOSEPH LEIDY, Fresh-water Rhizopoda of North America. LIDDELL and SCOTT, Greek-English Lexicon. SIR CHARLES LYELL, Antiquity of Man. SIR CHARLES LYELL, Principles of Geology. JOSEPH LE CONTE, Evolution and its Relation to Religious Thought. JOSEPH LE CONTE, Elements of Geology. C. S. MINOT, Human Embryology. ST. GEORGE MIVART, The Genesis of Species. ST. GEORGE MIVART, Lessons in Elementary Anatomy. ST. GEORGE MIVART, The Common Frog. ST. GEORGE MIVART, The Cat. A. M. MARSHALL, Vertebrate Embryology. HENRY C. MCCOOK, American Spiders. F. MAX MÜLLER, Anthropological Religion. C. LLOYD MORGAN, Animal Life and Intelligence. C. LLOYD MORGAN, Animal Biology. O. T. MASON, Woman’s Share in Primitive Culture. DANIEL OLIVER, Lessons in Elementary Botany. RICHARD OWEN, Anatomy of Vertebrates. A. S. PACKARD, Zoölogy. PARKER and HASWELL, Text-Book of Zoölogy. OSCAR PESCHEL, The Races of Man. E. P. POULTON, The Colours of Animals. J. W. POWELL, Truth and Error, or, The Science of Intellection. TH. RIBOT, Heredity. ERNEST RENAN, The Life of Jesus. G. J. ROMANES, Darwin and After Darwin. S. H. REYNOLDS, The Vertebrate Skeleton. OSCAR SCHMIDT, The Mammalia. OSCAR SCHMIDT, Descent and Darwinism. SCHAFER and THANE, Quain’s Elements of Anatomy. KARL SEMPER, Animal Life. HERBERT SPENCER, Principles of Biology. W. B. SCOTT, An Introduction to Geology. N. S. SHALER, First Book in Geology. J. B. SUTTON, Evolution and Disease. R. S. TARR, Elementary Geology. J. A. THOMSON, Outlines of Zoölogy. E. B. TYLOR, Anthropology. JAMES TYSON, The Cell Doctrine. LESTER F. WARD, Dynamic Sociology. LESTER F. WARD, Outlines of Sociology. ALFRED WEBER, History of Philosophy. A. D. WHITE, A History of the Warfare of Science with Theology. A. WEISMANN, Essays upon Heredity. A. WEISMANN, The Germ-Plasm. A. R. WALLACE, The Malay Archipelago. A. R. WALLACE, Darwinism. E. B. WILSON, The Cell in Development and Inheritance. R. WIEDERSHEIM, Comparative Anatomy of Vertebrates. R. WIEDERSHEIM, The Structure of Man. C. F. WINSLOW, Force and Nature. WILLIAM WHEWELL, History of the Inductive Sciences. B. G. WILDER, Anatomical Technology. B. G. WILDER, Article “Brain,” Reference Handbook of the Medical Sciences. ERNST ZIEGLER, General Pathology.

SECTION IX.

GLOSSARY.

GLOSSARY.

=A-chro´ma-tin= [Gr. _a_-priv.; _chroma_, color.] The nuclear hyaloplasm.

=A-chro-ma-top´si-a= [Gr. _a_-priv.; _chroma_, color; _opsis_, sight.] Color-blindness.

=Ac-ti-no-zo´a= [Gr. _aktis_, ray; _zoon_, animal.] A division of Cœlenterates embracing the sea-anemones and coral-polyps.

=Al-lan´to-is= [Gr. _allas_, sausage; _eidos_, form.] A membranous, sack-like appendage developed from the hinder part of the embryonic alimentary tract and which serves the purpose of effecting oxygenation and other changes in the blood in reptiles, birds, and mammals.

=Am-blyp´o-da= [Gr. _amblys_, blunt; _pous_, foot.] An extinct order of ungulates having elephantine feet and whose navicular bone was supported by the cuboid.

=Am-blys´to-ma= [Gr. _amblys_, blunt; _stoma_, mouth.] A genus of amphibians remarkable for the transformations they undergo. When undeveloped they represent the formerly recognized genus _Siredon_. Some species are called _axolotls_.

=Am´i-a= [Gr. _amia_, a kind of tunny.]

=Am-i-to´sis= [Gr. _a_-priv.; _mitos_, thread.] Direct cell-division; cell-division without the formation of nuclear figures.

=Am´mon-ites= [Egyptian _Amon_.] Fossil cephalopod shells.

=Am´nion= [Gr. _amnion_, fœtal membrane.] A membranous sack containing fluid which envelopes the embryo in the classes of reptiles, birds and mammals.

=A-mœ´ba pro´te-us= [Gr. _amoibe_, change; Proteus.] A unicellular animal; a Protozoan.

=Am-phib´i-a= [Gr. _amphi_, double; _bios_, life.] A class of vertebrates whose young are fish-like and have gills: the skull has two condyles and a parasphenoid.

=Am-phi-mix´is= [Gr. _amphi_, double; _mixis_, mingling.]

=Am-phi-ox´us= [Gr. _amphi_, double; _oxys_, sharp.] A small worm-like vertebrate whose body tapers at both ends. The skeleton is notochordal; skull, brain, auditory, and renal organs are absent.

=An-ab´o-lism= [Gr. _ana_, up; _ballo_, throw.] Constructive metabolism; the series of chemical changes by which a cell builds up simple and stable food into the highly complex and unstable living material.

=An-ap-to-mor´phus= [Gr. _an_-priv.; _hapto_, fasten; _morphe_, shape.]

=An-gi-o-sper´mæ= [Gr. _angeion_, vessel; _sperma_, seed.] Plants whose seeds are contained in a closed seed-vessel.

=An-nu-la´ta= [Lat. _annulatus_, ringed.] A division of Vermes, including marine worms, leeches, and earthworms.

=An-the-rid´i-a= [NL., < _anthera_, anther; Gr. dim. _idion_.] The male sexual organ in cryptogams answering to the anthers in phanerogams.

=An-thro-po-pi-the´cus= [Gr. _anthropos_, man; _pithekos_, ape.]

=An´thro-poid= [Gr. _anthropos_, man; _eidos_, form.] Manlike: said especially of the gibbons, orangs, gorillas, and chimpanzees.

=An-ti-tox´ine= [Gr. _anti_, opposed to; _toxikon_, poison.]

=A-nu´ra= [Gr. _an_, not; _oura_, tail.] An order of amphibians without a tail in the adult, including the toads and frogs.

=A´phis= [Gr. _apheideis_, lavish.] In Entomology a genus typical of Aphididæ. An aphid; a plant-louse.

=Ap-pen´dix ver-mi-for´mis= [Lat. _appendo_, to hang from; _vermis_, worm; _forma_, form.] A vestigial structure attached to commencement of the large intestine.

=A-rach´ni-da= [Gr. _arachne_, spider.] A class of Arthropods embracing the spiders, mites, scorpions, etc.

=Ar-cel´la= [Lat. dim. _arca_, a box.] Belonging to a group of protozoans having a chitinous shell.

=Ar-chæ´an= [Gr. _archaios_, ancient.] Pertaining to the oldest strata of rocks in geological history.

=Ar-chæ-op´ter-yx= [Gr. _archaios_, ancient; _pteryx_, bird.] A fossil bird with reptilian characteristics.

=Ar-che-go-sau´rus= [Gr. _archegos_, beginning; _sauros_, lizard.] A carboniferous amphibian (labyrinthodont.)

=Ar´go-naut= [Gr. _argo_, swift; _nautes_, sailor.]

=Ar-ma-dil´los= [Sp. dim. of _armado_, armed.] Edentate mammals having a carapace formed by ossification of the greater part of the skin and the union of the bony scutes.

=Ar-throp´o-da= [Gr. _arthron_, joint; _pous_, foot.] A branch of animals (invertebrates) with jointed legs, as insects, spiders, and crabs.

=As´ter= [Gr. _aster_, star.]

=As-ter-oi´de-a= [Gr. _aster_, star; _eidos_, form.] Echinoderms having radiating arms with ambulacral grooves below, embracing the true star-fishes.

=At´a-vism= [Lat. _atavus_, grandfather.] Reversion; recurrence to an ancestral type.

=At´e-les= [Gr. _ateles_, imperfect.]

=Au´ri-cles= [Lat. _auricula_, little ear.] A chamber of the heart which receives blood from the veins and transmits it to the ventricle.

=A´ves= [Lat. pl. of _avis_, bird.] Birds, a class of vertebrata.

=Ba-cil´lus= [Lat. _bacillum_, a little stick.] A genus of bacteria consisting of rod-like cells. They multiply by transverse division and by the formation of endogenous spores. Unicellular plants.

=Bac-te´ri-a= [Gr. _bakterion_, stick.] Microscopic unicellular plants. A genus of Schizomycetes (fission-fungi).

=Bal-a-no-glos´sus= [Gr. _balanos_, acorn; _glossa_, tongue.] Supposed by some biologists to belong to the Chordata.

=Beams= [AS. _beam_, tree.] The main stem of a deer’s antler.

=Bel-em´nites= [Gr. _belemnon_, dart.] A belemnitoid cuttlefish.

=Bi´o-phores= [Gr. _bios_, life; _phero_, bear.] Biological units of hereditary mass.

=Bi´pes= [Lat. _bis_, twice; _pes_, foot.]

=Blas´tid= [Gr. _blastos_, sprout.]

=Blas-to-ge-net´ic= [Gr. _blastos_, a germ; _genesis_, generation.] Originating in the germ cells.

=Blas´tu-la= [Gr. _blastos_, sprout.] A stage in the growth of the embryo; a hollow sphere of one layer of cells enclosing a segmentation-cavity.

=Brach-i-op´o-da= [Lat. _brachium_, arm; Gr. _pous_, foot.] Molluscoid animals with bivalve shells, one of which is dorsal and the other ventral; also with brachial appendages coming from the sides of the mouth. Lamp shells.

=Brach´i-o-pod= [Vid. Brachiopoda.] Lamp shell.

=Bry-oph´y-ta= [Gr. _bryon_, moss; _phyton_, plant.] A division of the vegetable kingdom consisting of liverworts and mosses.

=Bry-o-zo´a= [Gr. _bryon_, moss; _zoon_, animal.] Moss animals.

=Ca-du-ci-bran-chi-a´ta= [Lat. _caducus_, falling; _branchia_, gills.] Urodeles that lose their gills before maturity.

=Ca-du-ci-bran´chi-ates= [Vid. Caducibranchiata.]

=Cal´li-thrix= [Gr. _kalos_, beautiful; _thrix_, hair.]

=Cal-a-mo-ich´thys= [Gr. _kalamos_, reed; _ichthys_, fish.]

=Ca´lyx= [Gr. _kalyx_, cover.] The outermost series of leaves (sepals) of a flower; usually green.

=Cam´bri-an= [_Cambria_, _Wales_.] The name given by Sedgwick to those Palæozoic rocks that underly the Silurian, in Cambria (or Wales).

=Car-bon-if´er-ous= [Lat. _carbo_, coal; _fero_, bear.]

=Car-i-na´tæ= [Lat. _carinatus_, keel-shaped.] Birds having a keeled (carinate) breast-bone.

=Car-niv´o-ra= [Lat. _caro_, flesh; _voro_, devour.] Flesh-eating mammals.

=Cas-tra´tion= [Lat. _castratus_.] Removal of the glands that bear the Germ-Cells.

=Cat-ar-rhi´næ= [Gr. _kata_, down; _rhis_, nose.] Old World monkeys. The septum of the nose is narrow; the tail is short and not prehensile.

=Cat´ar-rhines= [Vid. Catarrhinæ.] Old World monkeys.

=Ceb´i-dæ= [Gr. _kebos_, long-tailed monkey.] A family of New World monkeys.

=Ce´bus= [Gr. _kebos_, long-tailed monkey.]

=Cen-o-zo´ic= [Gr. _kainos_, new; _zoe_, life.] Relating to the Quaternary and Tertiary eras.

=Cen´ti-pede= [Lat. _centum_, hundred; _pes_, foot.] A many jointed myriapod having a pair of legs to each joint.

=Cen´tro-some= [Gr. _kentron_, center; _soma_, body.] A body just outside of the nucleus of a cell and that governs the mitotic phases of a cell.

=Ceph-a-lop´o-da= [Gr. _kephale_, head; _pous_, foot.] Molluscs with a subcentral head, a beaked mouth, and tentacles taking the place of feet, including cuttlefishes, etc.

=Cer´a-tites= [Gr. _keras_, horn; _ites_, like.] A fossil cephalopod with the habitation chamber short and sutural saddles mostly simple.

=Cer´a-to-dus= [Gr. _keras_, horn; _odous_, tooth.] So-called from the horn-like ridges of the teeth. A lung-fish.

=Cer-co-pi-the´ci-dæ= [Gr. _kerkopithekos_, a long-tailed ape; _eidos_ form.] A family of catarrhine anthropoidea.

=Cer-e-bel´lum= [Lat. dim. of _cerebrum_, brain.] A subdivision of the encephalon.

=Cer´e-brum= [Lat. brain.] A subdivision of the encephalon.

=Cer´e-bral= [Vid. Cerebrum.] Pertaining to the cerebrum.

=Ce-ta´ce-a= [Lat. _cetus_, whale.] An order of fish-like mammals including the whales and porpoises.

=Chei-rop´te-ra= [Gr. _cheir_, hand; _pteron_, wing.] Including the Bats,—an order of mammals.

=Chei-ro´tes= [Gr. _cheirotos_, having a hand.] A native lizard of Mexico.

=Che-lo´ni-a= [Gr. _chelone_, tortoise.] An order of reptiles, including the turtles and tortoises.

=Chi-mæ´roids= [Gr. _chimaira_, a fabled monster; _eidos_, form.] An order of elasmobranchii (holocephali) with opercular membrane and smooth skin.

=Chi´ro-mys= [Gr. _cheir_, hand; _mus_, mouse.]

=Chim-pan´zee= [W. Afr.] Anthropopithecus. A West African arboreal, anthropoid ape; five feet high; distinct eyelashes, eyebrows, and whiskers; very large ears. It approximates to man in its dentition and the length of its arms. Has darker hair than gorilla.

=Chi´tin-ous= [Gr. _chiton_, tunic.] Pertaining to chitin, the horny substance in the skin of insects.

=Chro´ma-tin= [Gr. _croma_, color.] Nuclear threads.

=Chor-da´ta= [Lat. _chorda_, chord.] A subkingdom of animals with a notochord persistent or evanescent.

=Chro´mo-somes= [Gr. _croma_, color: _soma_, body.] Nuclear threads.

=Chry´so-thrix= [Gr. _chrysos_, gold; _thrix_, hair.]

=Clo-a´ca= [Lat. _cloaca_, a common sewer.] The common cavity into which the digestive, urinary, and genital canals empty in most vertebrates below placentals, and in all mammalian embryos.

=Coc´ci= [Gr. _kokkos_, berry.] Pl. of _coccus_. Isolated spherical cells (bacteria).

=Co-coons´= [F. _cocon_, dim. of _coque_, shell; < Lat. _concha_, shell.] The protective envelopes spun by certain larval insects, as silkworms, in which they are inclosed in the chrysalis state.

=Co-do-si´ga um-bel-la´ta= [Gr. _kodon_, a bell; _sige_, silence; Lat. _umbella_, dim. of _umbra_, shade.]

=Cœ-cil´i-a= [Lat. _cæcus_, blind.] Footless amphibians of snake-like form; rudimentary eyes; no neck.

=Cœ-len-te-ra´ta= [Gr. _koilos_, hollow; _enteron_, intestine.]

=Cœ-len´ter-ate= [Vid. Cœlenterata.]

=Cϫlome= [Gr. _koilos_, hollow.] The body-cavity of a metazoan between the viscera and the body-wall.

=Combs= [AS. _camb_, crest or ridge.] The fleshy crests on the heads of roosters, etc.

=Con-dy-lar´thra= [Gr. _kondylos_, knuckle; _arthron_, joint.] An Eocene group of ungulates in which the astragalus is not interlocked laterally with the tibia and its head rounded.

=Co-nif´e-ræ= [Lat. _conus_, cone; _fero_, bear.] The pine family of trees.

=Co´nus ar-te-ri-o´sus= [_Latin phrase_.] The arterial, cone-shaped portion of the left ventricle of the heart.

=Co-rol´la= [Lat., dim. of _corona_, crown.] The inner set of leaves of flowers and usually bright-colored. The individual parts are called petals.

=Crests= [Lat. _crista_, tuft.] Projecting natural growths on the tops of animals’ heads and usually ornamental, as the cock’s comb, or the lengthened feathers of a bird.

=Cre-o-don´ta= [Gr. _kreas_, flesh; _odous_, tooth.] A group of fossil animals containing forms ancestrally related to existing Carnivora.

=Cre-ta´ceous= [Lat. _creta_, chalk.] Pertaining to the latter part of the Reptilian age.

=Cri-noi´de-a= [Gr. _krinon_, lily; _eidos_, form.] Stone-lilies; stalked star-fishes. A division of Echinoderms.

=Cri´noids= [Vid. Crinoidea.]

=Croc-o-dil´i-a= [Lat. _crocodilus_, lizard.] An order of reptiles including crocodiles, alligators, and gavials. They are the highest order of reptiles. In them the heart and brain approximate very closely to that of birds.

=Cros-sop-te-ryg´i-a= [Gr. _krossoi_, tassels; _pterygion_ dim. of _pteryx_, wing.] A group of fishes with paired, lobate fins, and with an endodermal skeletal, axis fringed with dermal rays.

=Crus-ta´ce-a= [Lat. _crusta_, crust.] A division of arthropods containing crabs, lobsters, shrimps, crawfish, barnacles, etc.

=Cryp´to-gams= [Gr. _kryptos_, hidden; _gamos_, marriage.] The lower of the two great subdivisions of the plant kingdom. They have no true flowers containing stamens, pistils, and seeds; they propagate by means of spores.

=Cten-oph´o-ra= [Gr. _kteis_, comb; _phero_, bear.] A subdivision of cœlenterates with paddle-like locomotive plates arranged in eight meridional rows on the outer surface of the body.

=Cyc-a-da´ce-æ= [Gr. _kykos_, African coco-palm.] The cycad family of plants (gymnospermous), of fern-like or palm-like aspect.

=Cys-toi´de-a= [Gr. _kystis_, bladder; _eidos_, form.]

=Cy-no-ceph´a-lus= [Gr. _kyon_, dog; _kephale_, head.]

=Cy´to-plasm= [Gr. _kyo_, be pregnant; _plasma_, < _plasso_, form.] Protoplasm; especially that portion of a cell apart from the nucleus.

=Dal´ton-ism= [Dalton, chemist, who had color-blindness.] Color-blindness, especially red-blindness.

=De-cid´u-ate= [Lat. _deciduus_, falling off.] Shed at periodic times.

=Des´mids= [Gr. _desmos_, band.] Unicellular plants of minute size; bright-green in color; mainly solitary, fresh-water algæ.

=Dev-o´ni-an= [Devonshire, England.] The name given by Murchison to Palæozoic rocks in Devonshire, England.

=Di´a-toms= [Gr. _dia_, through; _tome_, cutting.] Microscopic unicellular algæ inhabiting salt or fresh water. Each individual (frustule) consists of two flint valves which are more or less symmetrical. They are either isolated or attached together in a series.

=Di-cot-y-le´don-es= [Gr. _dikotylos_, with two hollows.] The most important and largest class of flowering plants. Characterized by having seeds with two cotyledons, exogenous stems, and leaves that are netted-veined; the parts of the flower mostly in fours or fives.

=Di-del´phi-a= [Gr. _di_-, two; _delphys_, womb.] A sub-class of mammals, as the Marsupials, having a double womb and no placenta.

=Dif-flu´gi-a pyri-form´is= [Lat. _diffluere_, to flow apart; _pyrum_, pear; _forma_, form.]

=Di-no-sau´ri-a= [Gr. _deinos_, terrible; _sauros_, lizard.] Mesozoic land reptiles.

=Dip´no-i= [Gr. _di_-, two; _pneo_, breathe.] Fishes with regular gills, a double or single lung, and nostrils inside as well as outside the mouth.

=Dro-ma-the´ri-um= [Gr. _dromos_, running; _therion_, small wild beast.]

=Dys-chro-ma-top´si-a= [Gr. _dys_, bad; _chroma_, color; _opsis_, sight.] Partial color-blindness; difficulty in distinguishing colors.

=E-chi-no-der´ma-ta= [Gr. _echinos_, hedgehog; _derma_, skin.]

=E-chi´no-derms= [Vid. Echinodermata.]

=Ech-i-noi´de-a= [Gr. _echinos_, hedgehog; _eidos_, form.] Echinoderms including sea urchins.

=Ec´to-derm= [Gr. _ektos_, outside; _derma_, skin.]

=Ec´to-plasm= [Gr. _ektos_, outside; _plasso_, form.]

=E-den-ta´ta= [Lat. _e_, out of; _dens_, tooth.] An order of placentals with a small, one-lobed cerebrum; without median, cutting teeth: including armadillos, ant-eaters, and sloths.