Part 18

=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.

=El-as-mo-bran´chi-i= [Gr. _elasmos_, metal plate; _branchia_, gills.] Fish-like vertebrates which have no membrane bones in the skull or the shoulder-girdle; five pairs of strap-like gills attached by their distal ends; claspers to the ventral fins of males; complicated brain with optic nerves forming a decussation.

=Em´bry-o= [Gr. _en_, in; _bruein_, swell.] The term applied to an animal in the earlier stages of development.

=Em-bry-ol´o-gy= [Gr. _embryon_, embryo; _logos_, < _lego_, speak.] The study of embryos.

=En´do-derm= [Gr. _endon_, within; _derma_, skin.]

=En´do-plasm= [Gr. _endon_, within; _plasso_, form.]

=En-ter-op-neus´ta= [Gr. _enteron_, intestine; _pneustos_, breathing.] Acorn-tongue worms. Smooth-bodied, footless worms, having a large exserted soft proboscis; breathing by a series of respiratory sacs opening into the digestive canal, and communicating externally by spiracles; nervous system situated above a seeming notochord. Balanoglossus. Included by some biologists among the chordata.

=E-o-hip´pus= [Gr. _eos_. dawn; _hippos_, horse.]

=E´o-cene= [Gr. _eos_, dawn; _kainos_, recent.]

=Ep-en-ceph´a-lon= [Gr. _epi_, upon; _enkephalos_, brain.] A fundamental subdivision of the brain (encephalon).

=Ep´i-blast= [Gr. _epi_, upon; _blastos_, bud.]

=E´quus= [Lat. horse.]

=E-ryth-ro-lam´prus= [Gr. _erythros_, red; _lampros_, shining.]

=Eu-ca-lyp´tus= [Gr. _eu_, good; _kalypto_, cover.] A large genus of evergreen trees of the myrtle family.

=Ev-o-lu´tion= [Lat. _e_, out; _volvo_, roll.]

=Ex-o-skel´e-ton= [Gr. _exo_, outside; _skeleton_, dried body.] External skeleton; bony or horny hardening of the integument.

=Fla-gel´lum= [Lat., dim. of _flagrum_, scourge.] A slender protoplasmic extension of a cell, for purposes of locomotion.

=Fo-ram-i-nif´e-ra= [Lat. _foramen_, opening; _fero_, bear.] A division of protozoans secreting a shell perforated by many minute apertures.

=Fos´sil= [Lat. _fodio_, dig.] Any organic body so situated in the earth, and so buried in solid rock or in earthy deposits, as to be capable of indefinite preservation.

=Gan´gli-on= [Gr. _ganglion_, tumor.] A swelling that consists of an aggregation of nerve-cells. It receives and discharges nervous impulses and serves to stimulate psychical and organic activities.

=Ga-noi´de-i= [Gr. _ganos_, brightness; _eidos_, appearance.]

=Gas-ter-op´o-da= [Gr. _gaster_, stomach; _pous_, foot.] Including all snails and slugs.

=Gas´tru-la= [Dim. of Lat. _gaster_, stomach.]

=Gem´mæ= [Lat. buds.]

=Geph-y-re´a= [Gr. _gephyra_, bridge.] A division of worms with an œsophageal nervous ring and ventral chord; no distinct segments or legs; a terminal or dorsal anus.

=Go´ni-a-tites= [Gr. _gonia_, corner; _lithos_, stone.] A genus of fossil Ammonites.

=Gor´gets= [Fr. _gorgette_, dim. of _gorge_, throat.] Throat-patches distinguished by color or texture, especially in humming birds.

=Grap´to-lites= [Gr. _graptos_, written; _lithos_, stone.] Fossil hydroids.

=Greg-a-ri´na= [Lat. _gregarius_, < _grex_, flock.] A genus typical of Gregarinidæ. _Gregarina gigantea_ is sixteen millimeters in length and is one of the largest unicellular animals known.

=Greg-a-rin´i-dæ= [Vid. Gregarina.] More or less elongated amœba-like Protozoa, having a well-defined cell-wall, and a “subcuticular” system of muscular fibrillæ; nucleus, but no contractile vacuole; reproduction by encystment and subdivision of the central cell mass or protoplasm, by which shelly psorosperms are formed and from which escape the moner-like young, which undergo a metamorphosis.

=Gro´mi-a o-vi-form´is= [Lat. _gromia_; _ovum_, egg; _forma_, form.] A characteristic imperforate foraminifer.

=Gym-no-phi´o-na= [Gr. _gymnos_, naked; _ophis_, serpent]

=Gym-no-sper´mæ= [Gr. _gymnos_, naked; _sperma_, seed.] Plants whose seeds are not contained in a closed seed-vessel, as Cycads and Conifers.

=Hap´a-le= [Gr. _hapalos_, gentle.]

=Ha-pal´i-dæ= [Gr. _hapalos_, gentle] A family of New World monkeys including the Marmosets.

=Hel-i-co-nid´æ= [N., < _heliconius_, of Helicon; idæ.] A family of butterflies.

=Hes-per-or´nis= [Gr. _hesperos_, western; _ornis_, bird.] Cretaceous carinate birds with rudimentary wings, short tail, and pointed teeth implanted in grooves.

=Hip-po-pot´a-mus= [Gr. _hippos_, horse; _potamos_, river.]

=Hol-o-ceph´a-li= [Gr. _holos_, whole; _kepale_, head.] A subdivision of Elasmobranchii in which the suspensorium of the lower jaw is continuous with the cranium, as chimæroids, etc.

=Hol-o-thu-roi´de-a= [Gr. _holos_, whole; _thouros_, rushing.] Worm-like echinoderms, with skin-like integuments, and circum-oral tentacles; including sea-cucumbers, sea-slugs, etc.

=Ho-min´i-dæ= [Lat. _homo_, man; idæ.] A family of primates restricted to mankind.

=Hy´a-lo-plasm= [Gr. _hyalos_, glass; _plasma_, < _plasso_, form.]

=Hy´dra= [Gr. _hydra_, Lernæan serpent, < _hudor_, water.] A fresh-water polyp, having the form of a cylindrical tube, surrounded at the mouth with a circle of thread-like tentacles, by which it captures its prey.

=Hy´droid= [Gr. _hudor_, water; _eidos_, form.] Resembling the _hydra_; pertaining to the Hydroidea.

=Hy-dro-zo´a= [Hydro-; _zoon_, animal.] Cœlenterates including Hydroids and jelly-fishes.

=Hy-lob-a-ti´næ= [Gr. _hylobates_, one who walks the wood.] An Asiatic subfamily of apes; the long-armed apes or gibbons.

=Hy-lob´a-tes= [Gr. _hylobates_.] A gibbon,—an Asiatic ape.

=Hy-ra-coi´de-a= [Gr. _hyrax_, shrew-mouse; _eidos_, appearance.]

=Ich-thy-or´nis= [Gr. _ichthys_, fish; _ornis_, bird.] Cretaceous toothed birds of tern-like form, with socketed acute teeth, and bi-concave vertebræ

=Ich-thy-o-sau´ri-a= [Gr. _ichthys_, fish; _sauros_, lizard.]

=Id´i-o-blast= [Gr. _idios_, individual; _blastema_, sprout.]

=In-fu-so´ri-a= [Lat. _in_, into; _fundo_, pour.] So called because including many animalcules that occur in infusions of decaying substances.

=In-sec´ta= [Lat. _in_, into; _seco_, cut.]

=In-sec-tiv´o-ra= [Lat. _insectum_, insect; _voro_, devour.]

=In-ver-te-bra´ta= [Lat. _in_, not; _vertebratus_, jointed.] Including all animals that do not possess a notochord or backbone: opposed to Vertebrata.

=In-ver´te-brates= [Vid. Invertebrata.]

=Ju-ras´sic= [Jura mountains.]

=Kaf´ir-boom= [Erythrina caffra.] A prickly-stemmed tree of South Africa.

=Kal´li-ma para-lek´ta= [Gr. _kallimos_, beautiful; _para_, along side of; _lektos_, picked out.]

=Keri-vou´la pic´ta.=

=Lab-y-rin´tho-donts= [Gr. _labyrinthos_, labyrinth; _odous_, tooth.] Extinct amphibians.

=Lac-er-til´i-a= [Lat. _lacertus_, lizard.]

=La-ge´na= [Gr. _lagynos_, flask.]

=La-mel-li-bran-chi-a´ta= [Lat. _lamella_, a plate; _branchia_, gills.] Bivalve molluscs.

=La-nu´go= [Lat. _lana_, wool.]

=Lar´væ= [Lat. pl. of _larva_, mask.] The early forms of animals when they are unlike the parent. In insects the first stages after leaving the eggs, preceding the pupa, as maggots or caterpillars.

=Lem-u-roi´de-a= [Lemur; Gr. _eidos_, appearance.] A sub order of Primates. Prosimiæ.

=Lep-i-do-si´ren= [Gr. _lepis_, scale; _siren_, a genus of amphibians.] One of the lung-fishes.

=Lep-to-car´di-i= [Gr. _leptos_, fine, small; _kardia_, heart.]

=Liv´er-worts.=

=Lon-gi-cor´ni-a= [Lat. _longus_, long; _cornu_, horn.] A division of beetles having very long filiform antennæ.

=Ma-caques´= [F., < Afr. _macaquo_.] Cercopithecine monkeys of the genus _macacus_. Their form is stout; large ischial tuberosities: muzzle considerably produced.

=Ma-ca´cus.=

=Mam´mal= [Lat. _mamma_, breast; suffix -_al_; in analogy with Animal. Dr. Th. Gill.] Vertebrate animal whose female has mammæ, or milk-secreting organs.

=Mam-ma´li-a= [Vid. mammal.]

=Man´tis= [Gr. _mantis_, prophet.] The mantises are insects noted for the manner in which they carry the large spinous fore legs when waiting for prey. They have the attitude, then, as if praying.

=Mar´mo-set.= A small South-American monkey.

=Mar-si-po-bran´chi-i= [Gr. _marsipos_, bag; _branchia_, gills.]

=Mar-su´pi-al= [Lat. _marsupium_, pouch.] Animals having a marsupium or pouch for retaining the young.

=Mas´to-don= [Gr. _mastos_, breast; _odous_, tooth.] An extinct elephant.

=Me-dul´la= [Lat. _medius_, middle.] A subdivision of the brain—that portion especially that is continuous with the spinal chord.

=Men-o-bran´chus= [Gr. _meno_, remain; _branchia_, gills.] A large American aquatic amphibian, of salamander-like form, with persistent gills, as the mud-puppy.

=Mens sana in corpore sano.= A Latin phrase meaning a sound mind in a sound body.

=Mes-en-ceph´a-lon= [Gr. _mesos_, middle; _enkephalos_, brain.] A fundamental segment of the brain.

=Mes´en-chyme= [Gr. _mesos_, middle; _enchyma_, infusion.]

=Mes´o-blast= [Gr. _mesos_, middle; _blastos_, germ.]

=Mes-o-glϫa= [Gr. _mesos_, middle; _gloia_, glue.]

=Mes-o-hip´pus= [Gr. _mesos_, middle; _hippos_, horse.]

=Mes-o-zo´ic= [Gr. _mesos_, middle; _zoe_, life.]

=Met-a-dis-coi´dal= [Gr. _meta_, after; _diskos_, disk; _eidos_, appearance.] Resembling a discoidal form.

=Met-a-mor´pho-sis= [Gr. _meta_, over; _morphe_, form.] The series of pronounced external changes through which an animal passes after leaving the egg-envelopes and before reaching sexual maturity.

=Met-a-phy´ta= [Gr. _meta_, above, higher; _phyton_, plant.]

=Met´a-plasm= [Gr. _metaplasmos_, transformation.]

=Met-a-zo´a= [Gr. _meta_, after, higher; _zoon_, animal.]

=Met-en-ceph´a-lon= [Gr. _meta_, after; _enkephalos_, brain.] A fundamental segment of the brain.

=Mi-cro-ceph-a´li-a= [Gr. _mikrokephalos_, small-headed.] Imperfect development of the cranium.

=Mi-cren-ceph-a´li-a= [Gr. _mikros_, small; _enkephalos_, brain.] Small-brained.

=Mi´cro-cosm= [Gr. _mikros_, small; _kosmos_, world.]

=Micro-gro´mi-a so-ci-al´is= [Gr. _mikros_, small; _gromia_; Lat. _socialis_ < _socius_, companion.]

=Mi-cro-les´tes.=

=Mi´das.= A wealthy king of Phrygia.

=Mi-o-hip´pus= [Miocene; Gr. _hippos_, horse.]

=Mi´o-cene= [Gr. _meion_, less; _kainos_, recent.]

=Mi-to´sis= [Gr. _mitos_, thread.]

=Mol-lus´ca= [Lat. _mollis_, soft.]

=Mon-o-cot-y-le´don-es= [Gr. _monos_, single; _kotyledon_, cup-shaped cavity.] A group of flowering plants in which the first leaves of the embryo are alternate, for which reason they are said to have one seed-leaf or cotyledon.

=Mon-o-del´phi-a= [Gr. _monos_, single; _delphys_, womb.] A sub-class of mammals having a single vagina and uterus; embryo attached by a placenta; brain has a corpus callosum. Includes all animals above Monotremes and Marsupials.

=Mon´o-tremes= [Gr. _monos_, single; _trema_, hole.] An order of ornithodelphians.

=Mor´u-la= [Lat. dim. of _morum_, mulberry.]

=Mul-ti-tu-ber-cu-la´ta= [Lat. _multus_, many; _tuberculum_, tubercle.]

=My-ce´tes= [Gr. _myketes_, bellower.]

=Myr-i-ap´o-da= [Gr. _myrios_, numberless; _pous_, foot.] Insects with numerous pairs of legs, as centipedes.

=Nau´ti-loids= [Gr. _nautilos_, sailor; _eidos_, like.] A group of cephalopods.

=Nau´ti-lus= [Gr. _nautilos_, sailor.] A cephalopod.

=Nem-a-thel-min´thes= [Gr. _nema_, thread; _helmins_, worm.]

=Nem-er-ti´na= [Gr. _nemertes_, unerring.] Worms with skin ciliated, proboscis retractile, and nervous, muscular, and vascular systems characteristically developed.

=Ne-o-lith´ic= [Gr. _neos_, new; _lithos_, stone.]

=Noc-ti-lu´ca mi-li-a´ris= [Lat. _nox_, night; _luceo_, shine; _miliarius_, < _milium_, millet.]

=No´to-chord= [Gr. _notos_, the back; _chorda_, a chord.] A cartilaginous rod found in the young chordate embryo in a situation that is later on occupied by the centers of the bodies of the vertebræ. It separates a dorsal nervous system from a ventral alimentary (digestive) canal. The notochord is persistent in its entirety in Leptocardians and Marsipobranchs and also in some pisces, as the sturgeon.

=O-don-tor´ni-thes= [Gr. _odous_, a tooth; _ornis_, bird.] Including all those extinct birds having teeth.

=Œ-soph´a-gus= [Gr. _oiso_, will bear; _phagein_, eat.] The gullet; the membranous tube through which food passes from the pharynx to the stomach.

=On-tog´e-ny= [Gr. _on_, being; _genesis_, origin.] The history of the evolution of the individual; the development of the individual.

=On-to-ge-net´ic= [Gr. _on_, being; _genesis_, origin.] Pertaining to ontogeny.

=On-y-choph´o-ra= [Gr. _onyx_, claw; _pherein_, bear.] Arthropods including only a single genus, the curious caterpillar-like Peripatus.

=Oösperm= [Gr. _oon_, egg; _sperma_, semen.] A fertilized ovum. The first stage in the existence of a human being is called oösperm.

=O-per´cu-lum= [Lat. lid.] The gill-cover.

=O-phid´i-a= [Gr. _ophis_, serpent.] Serpents; snakes.

=Op-po´nens Hal-lu´cis= [Lat. _ob_, _pono_, to place over against; _hallux_, great toe.] The name of a muscle in the foot.

=Or-do-vi´cian= [_ordovices_, ancient Celtic tribe in Wales.]

=Or-nith-o-del´phi-a= [Gr. _ornis_, bird; _delphys_, womb.] A sub-class of oviparous mammals.

=Or-o-hip´pus= [Gr. _oros_, mountain; _hippos_, horse.]

=Or-tho-cer´a-tites= [Gr. _orthos_, straight; _keras_, horn.]

=Os´te-o-blasts= [Gr. _osteon_, bone; _blastano_, sprout.]

=Os´te-o-clasts= [Gr. _osteon_, bone; _klao_, destroy.]

=Os´tra-co-derms= [Gr. _ostrakon_, shell; _derma_, skin.]

=Ovum= [Lat. _egg_.] Female germ-cell; female, encysted, sexual cell.

=O-vip´a-rous= [Lat. _ovum_, egg; _pairo_, produce.] Producing eggs that mature and are hatched outside the body.

=Pal´li-um= [Gr. _mantle_.]

=Pa-læ-o-lith´ic= [Gr. _palaios_, ancient; _lithos_, stone.]

=Pa-læ-o-zo´ic= [Gr. _palaios_, ancient; _zoe_, life.]

=Pan-do-ri´na mor´um= [Gr. Pandora; _moron_, mulberry.]

=Pan-gen´e-sis= [Gr. _pas_, all; _genesis_, origin.]

=Par-a-me´ci-um= [Gr. _paramekes_, of longish shape.]

=Par-then-o-gen´e-sis= [Gr. _parthenos_, virgin; _genesis_, origin.] Production of a new individual from a virgin female without intervention of a male; reproduction by means of unfertilized eggs.

=Per-en-ni-bran-chi-a´ta= [Lat. _perennis_, perpetual; _branchia_, gills.]

=Per-en-ni-bran´chi-ates= [Vid. Perennibranchiata.]

=Ped´al= [Lat. _pes_, foot.]

=Per´mi-an= [Perm, Russia.]

=Phan´er-o-gams= [Gr. _phaneros_, visible; _gamos_, marriage.] Flowering plants.

=Phos-phor-es´cence.=

=Phryn-o-ceph´a-lus mys-ta´ce-us.=

=Phy-log´e-ny= [Gr. _phylon_, tribe; _genesis_, origin.] The history of the evolution of a species or group; distinguished from ontogeny.

=Phy-lo-ge-net´ic= [Vid. phylogeny.] Pertaining to phylogeny.

=Pith´e-coid= [Gr. _pithekos_, ape; _eidos_, like.]

=Pith-e-can-thro´pus= [Gr. _pithekos_, ape; _anthropos_, man.]

=Pla-gi-os´to-mi= [Gr. _plagios_, oblique; _stoma_, mouth.] A division of Elasmobranchii, including sharks and rays.

=Pla-cen´tal= [Lat. _placenta_, cake.] So called on account of its shape. Pertaining to the _placenta_, the organ of attachment of higher vertebrate (monodelph) embryos to the wall of the uterus of the female.

=Plas´tids= [Gr. _plastos_, formed.]

=Plat-y-hel-min´thes= [Gr. _platys_, flat; _helminos_, worm.]

=Plat-y-rhi´næ= [Gr. _platys_, broad, flat; _rhis_, nose.] Monkeys of the New World having long tails and a wide septum to the nose.

=Pleur-a-can´thus= [Gr. _pleuron_, rib; _akantha_, thorn.]

=Pleu´ral= [Gr. _pleura_, rib, side.]

=Pli-o-hip´pus= [Pliocene; Gr. _hippos_, horse.]

=Pli´o-cene= [Gr. _pleion_, more; _kainos_, recent.]

=Plumes= [Lat. _pluma_, small soft feather.] Feathers, especially when ornamental or large; or tufts of large and ornamental feathers.

=Pneu-mo-coc´ci= [Gr. _pneumon_, lung; _kokkos_, berry.] Bacteria (spheroidal) found in those suffering from pneumonia.

=Pol-y-dac´tyl-ism= [Gr. _polys_, many; _daktylos_, finger, toe.] The possession of an abnormally large number of fingers or toes.

=Pol-y-mor´phism= [Gr. _polys_, many; _morphe_, form.] Exhibition by a group of animals, as a species, of different types of form or structure.

=Po-lyp´te-rus= [Gr. _polypteros_, many-winged.]

=Po-ly´o-don= [Gr. _polys_, many; _odous_, tooth.]

=Pol´yp= [Gr. _polys_, many; _pous_, foot.]

=Pol´y-the-ism= [Gr. _polys_, many; _theos_, god.]

=Po-rif´e-ra= [Lat. _porus_, pore; _fero_, bear.]

=Pre-Pa-læ-o-lith´ic= [Lat. _præ_, before; Palæolithic.] The period of time preceding the Ancient Stone Age.

=Pri-ma´tes= [Lat. _primus_, first.] An order of mammals.

=Pro-bos-cid´e-a= [Gr. _pro_, before; _bosko_, feed.]

=Pro-nu´cle-us= [Lat. _pro_, before; _nucleus_, kernel.]

=Pros-en-ceph´a-lon= [Gr. _pro_, before; _enkephalos_, brain.] A fundamental segment of the brain.

=Pro-to-hip´pus= [Gr. _protos_, first; _hippos_, horse.]

=Pro-toph´y-ta= [Gr. _protos_, first; _phyton_, plant.]

=Pro´to-plasm= [Gr. _protos_, first; _plasma_, < _plasso_, form.]

=Pro-top´te-rus= [Gr. _protos_, first; _pteron_, wing.]

=Pro-to-zo´a= [Gr. _protos_, first; _zoon_, animal.]

=Pseu-do-he-red´i-ty= [Gr. _pseudes_, false; Lat. _heredita_, heirship.]

=Pseu-do-po´di-a= [Gr. _pseudes_, false; _pous_, foot.]

=Psy-cho-zo´ic= [Gr. _psyche_, soul; _zoe_, life.]

=Pter-i-doph´y-ta= [Gr. _pteris_, fern; _phyton_, plant.]

=Pter-o-sau´ri-a= [Gr. _pteron_, wing; _sauros_, lizard.]

=Pti-lo´pus cinc´tus.=

=Pu´pa=, pl. =pupæ= [Lat. doll, girl, f. of _pupus_, boy.] The third stage of those insects that undergo a complete metamorphosis. Pupæ are often surrounded by protective envelopes called cocoons.

=Quad-ru´la sym-met´ri-ca.=

=Qua-ter´na-ry= [Lat. _quaternarius_, consisting of four.]

=Ra-ti´tæ= [Lat. _ratis_, raft.] A group of birds whose sternum is without a keel; aborted wings. Including ostriches, emus, moas, rheas, etc.

=Rhi-noc´e-ros= [Gr. _rhis_, nose; _keras_, horn.]

=Rhi-zop´o-da= [Gr. _rhiza_, root; _pous_, foot.]

=Ro-den´ti-a= [Lat. _rodo_, gnaw.]

=Ro-ta´li-a Frey´er-i= [Lat. _rota_, wheel; Freyer.]

=Ro-ta-to´ri-a= [Lat. _rota_, wheel.]

=Ro´ti-fer= [Lat. _rota_, wheel; _fero_, bear.]

=Ru´mi-nant= [Lat. _ruminans_, ruminate.]

=Sai´tis pu´lex.=

=Saur-u´ræ= [Gr. _sauros_, lizard; _oura_, tail.] Jurassic birds having lizard-like tails with distichous feathers, as Archæopterygidæ.

=Sca-phop´o-da= [Gr. _skaphos_, bowl, skiff; _pous_, foot.] A division of molluscs.

=Sep´al= [Lat. _separ_, separate.] One of the individual leaves of a calyx.

=Si-lu´ri-an= [Silures, ancient Celts in Wales.]

=Sim´i-a= [Lat. _simia_, ape.] A genus typical of Simiidæ and now restricted to the orang.

=Si-mi´i-dæ= [Lat. _simia_, ape.] A family of Old World Anthropoidea.

=Sim-i-i´næ= [Lat. _simia_, ape.] A subfamily of Simiidæ with robust form and molars tuberculated as in man and no ischial tuberosities, including Chimpanzees, Gorillas, and Orangs.

=Si´nus veno´sus= [Lat.] Venous cavity. (1) In higher vertebrates the main part of the auricular cavity. (2) In the lower vertebrates, a dilitation at the termination of venous channels, forming a separate chamber.

=Si-re´ni-a= [Lat. _siren_, siren.]

=Snags= [Norw. _snag_, a projecting point.] A branch on the antler of a deer.

=So-mat´ic= [Gr. _soma_, body.] Pertaining to the body.

=So-ma-to-ge-net´ic= [Gr. _soma_, body; _genesis_, generation, origin.] Originating in the body or soma through external influences.

=Sper-ma-to-zo´id= [Gr. _sperma_, seed, semen; _zoon_, animal.] Male germ-cell; male, flagellate, (“ciliated”) sexual cell. At one time supposed to be minute parasites in the semen, hence often called _spermatozooa_.

=Sphinx fu-ci-form´is.=

=Spon´gi-o-plasm= [Gr. _spongion_, little sponge; _plasso_, form.]

=Steg-o-ceph´ala= [Gr. _stego_, cover; _kepale_, head.] Another name for Labyrinthodonts.

=Sty-lo-nych´i-a.=

=Su-pra-œ-soph-ag´e-al= [Lat. _supra_, above; œsophagus.]

=Tar´si-us= [Gr. _tarsos_, any flat surface.]

=Tax-o-nom´ic= [Gr. _taxis_, orderly arrangement; _nemein_, distribute.] Pertaining to systematic classification.

=Tel-e-os´to-mi= [Gr. _teleos_, perfect; _stoma_, mouth.] A division of fishes with well-developed dentary and maxillary and membrane bones; includes all fishes except Elasmobranchii and lower forms.

=Tel´e-osts= [Gr. _teleos_, perfect; _osteon_, bone.] A subdivision of Teleostomi that includes most fishes; decussation of optic nerves; non-contractile arterial bulb.

=Ter´ti-a-ry= [Lat. _tertius_, third.]

=Tet´ra-o cu´pi-do= [Lat. _tetrao_, pheasant; _Cupido_, the God of Love.]

=Thal-am-en-ceph´a-lon= [Gr. _thalamos_, chamber; _enkephalos_, brain.] A fundamental segment of the brain.

=Thal´a-mi= [Gr. _thalamos_, chamber.] The lateral boundaries of the thalamencephalon.

=Thal´loph´y-ta= [Gr. _thallos_, young branch; _phyton_, plant.]

=The-ro-mor´pha= [Gr. _ther_, beast; _morphe_, form.]

=Tho-mi´sus cit´re-us.=

=Ti-mor´.=

=Top´knots.= Crests or tufts of feathers growing on the heads of birds.

=Toxalbu´min= [Gr. _toxikon_, poison; _albumin_, < Lat. _albus_, white.]

=Tri-as´sic= [Gr. _trias_, three.]

=Tri´lo-bites= [Gr. _treis_, three; _lobos_, lobe.]

=Tu-ni-ca´ta= [Lat. _tunica_, tunic.] A class of Chordata called Sca-squirts or Ascidians.

=Tynes= [AS. _tind_, prong.] The spike or prong of an antler.

=Un-gu-la´ta= [Lat. _unguis_, nail.] The order of hoofed mammals.

=U-ro-de´la= [Gr. _oura_, tail; _delos_, manifest.] The tailed Amphibians.

=U´te-rus= [Lat. _uterus_, womb.] The organ of a female animal in which the young are protected and developed before birth.

=Vac´u-ole= [Lat. _vacuus_, empty.] The little cavities in cells containing watery solutions.

=Ves´i-cle= [Lat. _vesicula_, little bladder.] Synonymous with vacuoles.

=Ve´na ca´va= [Lat.] _Hollow vein._ Either of the two great veins that empty into the right auricle of the heart.

=Ven´tri-cles= [Lat. _ventriculus_, little belly.] One of the cavities of the heart or brain.

=Ven´tral= [Lat. _venter_, belly.] Applied to the front (under) side of the body.

=Ver´mes= [Lat. _vermis_, worm.]

=Ver-te-bra´ta= [Lat. _vertebratus_, jointed.]

=Ver´te-brate= [Lat. _vertebratus_, jointed.]

=Vi-vip´a-rous= [Lat. _vivus_, alive; _pario_, bear.] Applied to animals which bring forth their young alive.

=Vis´ce-ra= [Lat. _viscera_, organs.] The internal organs of the body.

=Vol´vox glo-ba´tor= [Lat. _volvo_, roll; _globatus_, made into a ball.]

=Wat´tles= [AS. _watel_, hurdle.] Fleshy, naked processes depending from the neck or head of a bird.

FOOTNOTES.

[1] One cubic millimeter of human blood alone, not to mention other tissues of the body, contains over five million cells.

[2] Except in the maturation of _ova_ and _spermatozoids_.

[3] Bradford.

[4] Bradford.

[5] Socially, morally, and religiously.

[6] Lyell.

[7] Readers not familiar with Elementary Zoölogy will do well to consult the Classification of Animals in Section VII.; and also the Diagram of Development.

[8] Wallace.

[9] Belt.

[10] Wallace.

[11] Wallace.

[12] Wallace.

[13] Darwin.

[14] Darwin.

[15] Lloyd Morgan.

[16] Clodd.