INDEX. 



429 



Dor'sal vessel, in insects, 359. 

 Dorsibranchia'ta (Lat. dorxnm, 



back : Gr. /3payx ia > gi^ 8 )' m l- 

 lusks with gills attached to the 

 back, xxii. 



Drift formation, 650, 684. 



Duc'tus (Latin), a duct, or tube, 

 which conveys away the secretion 

 of a gland. 



Duode'num (Lat. duodecim, twelve), 

 the first portion of the small in- 

 testine, which in the human sub- 

 ject equals the breadth of twelve 

 fingers. 



Du x ra master, 85. 



E, Ex, a Latin prefix, signifying 

 generally "without," or "from," 

 as Edentata, Exosmose; which see. 



Ear, the, 145161. 



Earth's crust, structure of the, 642 

 655. 



Echinas'ter sanguin'olentus, meta- 



I Emar'ginate (Lat. cmargino, to re- 

 the i move an edge), when an edge or 



morphoses of the, 557, 558. 

 Ech'ini,anorderofEchinoderms,xxiii. 

 Echin'oderms (Gr. 6%Tvoe, a hedge- 



margin has, as it were, a part bit- 



ten out. 

 Em'bryo (Latin), the earliest stage 



of the young animal before birta, 



433. 

 Embryol'ogy, 429509 ; the egs, 



429 446 ; development of the 



young, 447 499 ; zoological im- 



portance of embryology, 500 



509. 

 Enal'iosaur (Gr. fvaXios, marine ; 



aavpng, a lizard), an extinct order 



of marine gigantic reptiles allied 



to crocodiles and fishes. 

 Enceph'ala(Gr.ev,in; KtQaXq, head), 



molluscous animals which have a 



distinct head. 

 Endogenous, increasing by inwxrd 



addition, as the palm tree, 72. 

 Endosmose x and exosmose\411,413. 

 Entomol'ogy (Gr. tvro/ia, insects ; 



, a discourse), the depart- 

 ment of natural history which 

 treats of insects. 



hog; Sepfj,a, skin), the class of j Entomos'tracans (Gr. Ivrofjia, in- 

 radiated animals, most of which j sect ; oorpa/cov, shell), small crus- 

 have spiny skins, xxiii. taceans, many of which are en- 



Echin'oderms, 661 ; internal organs | closed in an integument, like a 



of the, 316 ; jaws of the, 335. 



bivalve shell, xxii. 



Eden v tata (Lat. ex, without, dens, a Entozo^a (Gr. fj/rog, within; Zwov, 

 tooth), a class of mammals, inj animal), animals which exist with- 

 which the teeth are in some degree I in other animals, 

 incomplete ; as in the armadillo, j Eocene^ (Gr. nog, the dawn ; KCIIVO<;, 



Eden'tulous, from the Latin word 

 for toothless. 



Egg, the, all animals produced from, 

 433, 434 ; form, 435 ; formation, 

 436446 ; development of the 

 young, 447 479 ; structure as 



recent), the stage of the tertiary 

 period, in which the extremely- 

 small proportion of living species 

 indicates the first commencement 

 or dawn of the existing state of 

 animate creation, 650. 



just laid, 480 ; changes in, during Epider'mal (Gr. t7riBipfj.i, the cuti- 



incubation, 499. 



Elementary structure of organized 

 bodies, 35 ; of tissue, 56. 



El'ytra (Gr. tXvrpov, a sheath), the 

 wing sheaths formed by the mo- 

 dified anterior pair of wings of 

 beetles. 



cle), belonging to the cuticle or 

 scarf skin, 413. 



Epister'nal (Gr. e-m, upon ; artpvov, 

 the breast-bone), the piece of the 

 segment of an articulate animal 

 which is immediately above the 

 middle inferior piece, or sternum. 



