IS"DEX. 



Acceleration, vi, 142, 182, 287, 383. 



Acceleration and retardation, 2, 11, 125, 

 127, 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. 



Amhlydomis sinosus, 375. 



Amblyopsis, 196. 



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

 360, 368, 371, 374, 



Amblystoma, 4. 



Amblijstoma mavortium^ 88. 

 tigrhmm, 89. 



Ameiva 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. 



Aniiui'us, 4. 



Amiurus albidics, 85. 

 lynx, 85. 



Ammocoetes, 316. 



Ammonites, 18. 



Amoeba, 440, 445, 446, 450. 

 Amoebodonts, 247, 248, 257. 

 Araphioxus, 182. 

 Amphiuma, 333. 

 Anaptomorphus cemiilus, 279. 



homnnculus^ 279. 

 Ancestral types of mammalia cducabilia, 



266. 

 Anchitherium awclianense, 275. 

 Ancisfrodon cordortrix, 197. 



piscivorus, 197. 

 Anelytropidae, 337. 

 Anguidae, 337. 

 Aniellidae, 337. 

 Anisonchus, 245, 359. 

 Anolis, 4. 



Anoplotberium, 247, 265, 370. 

 Anthracotherium, x. 

 Anthropoidea, 342, 343. 

 Antiarcha, 323. 

 Antilocapra, 383. 

 Antiodonts, 247. 

 Anura, 331, 332, 333. 

 Aphelops meffalodvs, 369. 

 Aphododiridae, 328. 

 Appendicularia, 322. 

 Archcelu7'us dibilis, 375. 

 Archaesthetism, xii, 406, 414, 419, 421. 

 Arcliaeopteryx, 340. 

 Arcifcrous anura, 95, 218. 

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

 399, 401. 

 omnivora, 199. 

 Ascertained cases of transition, 87. 

 Ascidia, 399. 

 Atrophy, 13, 127. 



