=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-glœ´a= [Gr. _mesos_, middle; _gloia_, glue.] =Mes-o-hip´pus= [Gr. _mesos_, middle; _hippos_, horse.] =Mes-o-zo´ic= [Gr. _mesos_, middle; _zoe_, life.]