INDEX. 



Note. — An asterisk (*) after the number of a page indicates that there is a reference on the 

 page to a. figure of the species or object mentioned ; and a section-mark (§) implies that the page 

 contains a definition, explanation, or characteristic of the word or object mentioned. 



Abich, analysis of trachyte, 



Abies, 450, 497. 

 Abyssal zone, 611. 

 Abyssinia, plateau of, 27. 

 Acacia, 514, 515. 

 Acadian epoch, 163, 166. 



Triassic, 404. 

 Acalephs, 117,* 127,§ 129,§ 341. 



range of, in time, 386. 

 Acanthospongia, 207. 

 Acanthotelson Eveni, 342. 



Stimpsoni, 364,* 342. 

 Acanthoteuthis, 441. 



antiquus, 440.* 

 Accipenser. 264. 

 Accumulation of rock-material, 



615. 

 Acephals, 124, 125. § 



range of, in time, 337.* 

 Acer, 459, 497. 



obtusilobum, 459. 

 Aceratherium, 506. 

 Acetabu lifers, 439. 

 Acidaspis, 240, 249, 253. 



Barrandei, 247. 



range of, in time, 387.* 

 Acidic series of igneous rocks, 



66, § 748, 832. 

 Acid spring, 234. 

 Aclis robusra, 342. 

 Acrodonts, 338. § 

 Acrodus, 428, 475. 



minimus, 262 * 429. 



nobilis, 262* 449. 

 Acrolepis, 372. 



Sedgwickii, 372. 

 Acrostichites oblongus, 409. 

 Acrogens, 133. § 



Age of, 139. 



range of, in time, 140.* 

 Acrotreta, 173, § 190. 



gemma, 250. 



subconica, 250. 

 Actaeonella, 475. 

 Actaeonina, 475. 

 Actinia, 117-* 

 Actinoid Polyps, 130. § 

 Actinoiite, 54. *§ 

 Actinolvte, 74. § 

 Actinocrinus, 303, 341. 



(Batocrinus) longirostris, 

 118, 129.§ 298,* 303. 



proboscidialis, 298* 303. 



pulcher, 247. 



tenuiradiatus, 191. 

 Actinocyclus Ehrenbergii, 496. 

 Actinoptvchus undulatus,496.* 



senarius, 134,* 496.* 

 Adacna Titrea, 610. 



Aderholt, analyses of Lycopod 



ash, 365, 366. 

 Adiantites, 348. 

 Adie, dilatation of rocks, 720. 

 Adipocere, 617. 



Silurian, 612. 

 Adirondack iron-mines, 151. 



mountains, 390, 796, 814. 

 Adjutant, 516. 

 Admete viridula, 553. 

 JEchmodus, 442.* 



angulifer, 449. 



Leachii, 449. 

 ^glea, 350. 

 JEglina binodosa, 192. 

 JSpyornis, 580. 

 iEtiiophyllum speciosum, 426. 



stipulare, 426. 

 Africa, Cretaceous in, 470. 



mean height of, 14. 



plateaus of, 22 



system in reliefs of, 27.* 



Tertiary in, 512. 

 Agalmatolite, 58. § 

 Agaricia, 620. 

 Agassiz, A., Echfini, 595. 



Tilibiche, Peru, 783. 

 Agassiz, L., criteria of rank 

 among animals, 592. 



Drift, 532, 536. 



glaciers, 694, 702. 



Man's position in classifica- 

 tion, 578. 



names of Ages, 138. 



tails of fishes, 412. 

 Agassizocrinus, 341. 

 Agate, 53. § 

 Age of Acrogens, 139. 



of Fishes, 140, 254. 



of Invertebrates, 162. 



of Mammals, 589. 



of Man, 141, 527. 



of Reptiles, 403. 

 Agelacrinites Billingsii, 203. 



Buchianus, 207. 

 Ages, names of, 140. 



reality of, 137. 



subdivision into, 138. § 

 Aglaspis, 168, 178. 

 Agnostus, 168, 178, 180, 188, 

 190, 253. 



Acadicus, 175,* 176. 



integer, 180. 



lobatus, 202,* 204. 



nobilis, 178. 



pisiformis, 208. 



princeps, 180. 



rex, 180.* 

 Agraulos, 168, 178, 189. 

 Agriochoerus, 511. 



Agriochoerus antiquus, 511. 



major, 511. 

 Aiguille, 651. § 

 Air, oxygen in, 49. 

 Air-breathers, first of, 273, 301. 

 Alabama, Carboniferous in, 

 291, 811. 



Cincinnati in, 197. 



Clinton in, 219. 



Cretaceous in, 455, 456. 



glaciers in, 537. 



Millstone-grit in, 311, 320. 



Subcarboniferous in, 294,305. 



Tertiary in, 491, 494. 



Triassic in, 423. 



in the Cretaceous, 479. 



period, 490, 494, 509, 523. 

 Alabaster, 56. § 

 Alaska, Triassic in, 407. 

 Albertite, 296, 315, 316. 

 Albian group, 470. 

 Albite, 54.§ 

 Albite-felsyte, 71. § 

 Alca impennis, 580. 

 Alcyonium, 130. § 

 Alcyonoid Polyps, 130.§ 

 Alder, 515. 

 Alethopteris, 330, 348, 370. 



discrepans, 271. 



lonchitica, 326,§ 330, 331. 



marginata, 331. 



Owenii, 297. 



Serlii, 330. 

 Aletornis gracilis, 510. 



nobilis, 510. 

 Aleutian Islands, 35. 

 Alga?, 133, 134,§ 139,* 140, 61L 

 678. 



Carboniferous, 296, 331. 



Devonian, 257, 277. 



Silurian. 169, 186, 223, 242. 



the earliest plants, 140.* 



in hot waters, 611 

 Alleghany Mts., 390, 395, 789, 

 795. 



Carboniferous in, 291. 

 Allen, J. A., burning of coal 



beds, 763. 

 Allen, T. J., Pele's hair, 743. 

 Alligator, 510. 

 Allorisma subcuneata, 332,* 



342. 

 Alluvial fans, 659. § 



formations, origin of, 657. 

 Alluvian epoch, 543. 

 Alluvium, 68,§ 544.§ 

 Almond, 514. 

 Alnus, 497. 



Kefersteinii, 498, 514. 

 Alpine plants, 609. 



