424 



INDEX. 



external j ointed skeletons or j oin ted 

 limbs ; as the leech, the spider, the 

 gnat, xxii. 



Articula v ta, or Artic'ulates, 70 ; ner- 

 vous system, 115; jaws, 337; of 

 the tria's period, 665, 670. 



Ascid'ian (Gr. daicoc, a bottle), shell- 

 less acephalous mollusks, shaped 

 like a leathern bottle. 



Assimilation, the change of blood 

 into bone, muscle, &c. 401. 



Asteria x dae (Gr. darpov, a star), 

 the family of star-fishes, xxiii. 



Astre'idas, a family of polyps, found 

 in the Coral-rag, 6/4. 



Bas'ilosaurus, an extinct cetacean, 

 680. 



Batra'chians (Gr. fiarpaxoQ, a frog), 

 the order of reptiles including the 

 frog, xxi. 



Batra x chians, peculiar species of, 626. 



Belem'nite (Gr. fiiXspvos, a dart), 

 an extinct genus of mollusks ; 

 animals allied to the sepia, and 

 provided with a long, straight, 

 chambered conical shell in the in- 

 terior of the body, 673. 



Bi, or Bis, a Latin prefix, signifying 

 "twice," as in the following words : 



Bi'fid, cleft into two parts, or forked. 



Au'ditory (Lat. audio, I hear), per- 1 Bf furcate, divided into two prongs 



taming to the sense of hearing. 

 Au'ricle(Lat. auricula),^ cavity of the 



heart, shaped like a little ear,36 1 . 



Australia, fauna of, 615. 



Autoch'thonoi (Greek), Aborigines, 

 or first inhabitants, theory of, ap- 

 plied to the distribution of ani- 

 mals, 631. 



Automatic (Gr. avro^aroQ, self- 

 moving), a movement in a living 

 body without the intervention or 

 excitement of the will. 



Aves (Latin), birds ; the second class 

 of vertebrate animals, xxi. 



Axil'la (Lat. arm-pit), applied to 



or forks. 

 Bilateral, having two symmetrical 



sides. 



BHobed, divided into two lobes. 

 Bipartite, divided into two parts. 

 BPpeds (Lat. bis, two, pes, a foot), 



animals with two feet, as man and 



birds. 



Bird tracks, fossil, 670. 

 Birds, the second division of the ani- 

 mal kingdom, xxi. 

 Birds, muscular system of, 227 ; 



stomach of, 330." 

 Bis (Latin), two, or twice; used in 



composition only. 



other parts of the animal body | B? valve, a shell of two parts, closing 



which form a similar angle. 

 Ax'olotl, a genus of reptiles, 626. 



like a double door, 662. 

 Blas'toderm, the embryonic germ. 



Az'ygos (Gr. a, without; vyoc, | Blood, the, and circulation,350 375. 



yoke), single, without fellow. i Blood, the, its constituents, 350 



351 ; corpuscles, 352; colour, 

 BAC'ULITE (Lat. baculus, a staff), an i 



extinct genus of mollusks, allied j 



to the nautilus, which inhabited a j 



straight-chambered shell, resem- j 



bling a staff. 



353 ; its presence an essential 

 condition of life, 354; circulation, 

 361 375; changes that it under- 

 goes in circulation, 395. 

 Bone, analysis of, 238 ; basis, 239 ; 



Bal'anoids (Gr. (3a\avo, an acorn), I microscopic structure, 240 ; the 

 a family of sessile cirripeds, the j various bones of the human ske- 

 shells of which are commonly j leton, 235, 241278. 

 called acorn shells. j Bot'ryoi'dal (Gr. porpvs, a bunch of 



Bar'nacle ; see Anatifa. grapes), having the form of a 



Bas'ilar (Lat. basis, a base), belong- i bunch of grapes, 

 ing to the base of the skull. I Bould'ers, 684. 



