i:n"dex. 



Acceleration, vi, 142, 182, 287, 883. 



Acceleration and retardation, 2, 11, 125, 

 12Y, 297. 



Acrania, 322, 323. 



Actinia, 33. 



Actinophrys, 27, 187, 192. 



Actinopteri, 325, 326. 



.^sthetophore, 419. 



Aethalium, 396. 



Agassiz, vii, 8, 45, 58, 60, 61, 62, 83, 91, 

 92, 103, 121, 124. 



Ageniosus, 327. 



Allen's "Anatomy," 272, 279. 



Allen, H., 115,242. 



Allen, Keen, and Pepper on " Universal 

 Hyperostosis," 183. 



Allman, Prof., 415. 



Altruism, xi, 237, 441, 453. 



Amblydonus sinosus, 375. 



Amblyopsis, 196. 



Amblypoda, 278, 342, 343, 344, 346, 348, 

 360, 368, 371, 374. 



Amblystoma, 4. 



Amblystoma mavortium, 88. 

 t'griinim, 89. 



Amciva pleii, 87. 



American Association for the Advance- 

 ment of Science, x, xi, xii, xiii. 



"American Naturalist," ix, xi, xii, xiii, 

 244, 277, 359, 363, 383. 



Ametabola, 316. 



Amiurus, 4. 



Amiuiics albidus, 85. 

 lynXy 85. 



Ammocoetes, 316. 



Ammonites, 18. 



Amoeba, 440, 445, 446, 450. 

 Ama?bodonts, 247, 248, 257. 

 Amphioxus, 182. 

 Amphiuma, 333. 

 Anaptomorphus eemulus, 279. 



hommiculus, 279. 

 Ancestral types of mammalia cducabilia, 



266. 

 Anchitherium aurelianense, 275. 

 Ancisfrodon coiiioririx, 197. 



piscivorns, 197. 

 Anelytropidae, 337. 

 Anguidse, 337. 

 Aniellidse, 337. 

 Anisonchus, 245, 359. 

 Anolis, 4. 



Anoplotherium, 247, 265, 370. 

 Anthracotherium, x. 

 Anthropoidea, 342, 343. 

 Antiarcha, 323. 

 Antilocapra, 383. 

 Antiodonts, 247. 

 Anura, 331, 332, 333. 

 Aphelops megalodiis, 369. 

 Aphododiridae, 328. 

 Appendicularia, 322. 

 Archcelurus debilis, 375. 

 Archaesthetism, xii, 405, 414, 419, 421. 

 Arcliaeopteryx, 340. 

 Arciferous anura, 95, 218. 

 Artiodactyla, 344, 368, 371-374, 375, 

 399, 401. 



omnivora, 199. 

 Ascertained cases of transition, 87. 

 Ascidia, 399. 

 Atrophy, 13, 127. 



