826 



INDEX. 



Texas, Subcarboniferous in, 293. 



Tertiary in, 491, 498. 



terraces in, 548. 

 Thallogens, 133.§ 

 Thanet sands, 512, 518. 

 Theca, 180, 372. 



corrugata, 180. 



gregarea, 178.* 



triangularis, 208. 



vaginula, 208. 

 Thecidea, first of, 448, 474. 

 Thecidium, 173,§ 174. 

 Thecocyathus rugosus, 448. 

 Thecodonts, 338, § 371. 



first of, 374, 376. 



range of, in time, 589* 592. 

 Thecodontosaurus, 338,§ 428. 

 Thecosmilia Tarquemi, 448. 

 Thelodus parvidens, 246.* 

 Thenaropus heterodactylus, 343. 

 Thermal springs, 401, 692, 719, 



729. 

 Thickness of stratified rocks, 



145, 657. 

 Thinolestes, 510. 

 Thinosaurus grandis, 510. 

 Thomson, \Ym., on length of 

 time, 591. 



on earth's loss of heat, 699. 

 Thoracosaurus Neocassariensis, 



467. 

 Thracia Conradi, 551. 

 Thrissops, 264.* 

 Thuia, 497. 

 Thuiopsis, 514. 

 Thuringia, Permian in, 369. 

 Thuvites articulatus, 449. 



divaricatus, 449. 

 Thylacotherium Broderipii, 446, 



448.* 

 Tiaropsis, 117.* 

 Tiburtine, 75. § 

 Tick, 121. § 



Tides and tidal currents, 659. 

 Tiger, 506. 508, 564. 

 Tile Clay, 513. 

 Tilestones, 164, 244. 

 Till, 66.§ 



Tillotherium hyracoides, 510. 

 Time, length of geological, 590. 

 Time-ratios, Cenozoic, 585. 



Mesozoic, 481. 



Paleozoic, 381. 

 Tinoceras grande, 510 

 Titanic iron, 59, § 74. 

 Titanotherium, 495, 506. 



Proutii, 506,* 511. 

 Titbonic group, 435. 

 Tivoli travertine beds, 692. 

 Toarcian group, 435. 

 Todtliegende, 369. 

 Tom Ball ridge, sections of, 



213.* 

 Tombigby sand, 456. 

 Tomitherium, 510. 

 Tomopteris, 123.§ 

 Tongrian group, 513. 

 Tookey, analysis of coal, 316. 

 Topaz, 58, §* 728. 

 Topographical effects of erosion, 



644. 

 Torbanite, 315, 316. 

 Torrent-portion of a stream, 



638. § 

 Torrid zone, 41. § 

 Totten, expansion of rocks, 700. 

 Tourmaline, 57,§* 727, 728. 

 Toxaster complanatus, 475,476. 

 elegans, 466, 468. 



Toxoceras, 462. § 



bituberculatum, 473,* 475. 

 Tracks. See Footprints. 

 Trachelomonas levis, 634.* 

 Traehium cyathiforme, 190. 

 Trachydoleryte, 78. § 

 Trachyte, 77,§ 707, 718, 736. 

 Trails. See Footprints. 

 Trains of bowlders, 529. 

 Translation-waves, 662. 

 Transportation by currents, 

 665. 



by icebergs, 686. 



by rivers, 647. 



by waves, 665. 

 Trap, 78,§ 49, 306. 



at Lake Superior, 185. 



distribution and formation of, 

 716. 



minerals of Nova Scotia, 418. 

 i in Triassic of Connecticut val- 

 ley, etc., 20,* 418,* 421, 

 452, 486, 722. 

 | Triassic, of uniform charac- 

 ter, 417. 

 Trapa natans, 135. § 



ash of, 366. 

 Travertine, 75,§ 692. 

 Trees, erect in rocks, 296, 356, § 

 436* 



protection by, 607- 



silicified, 693. 

 Tree-ferns, 258, 270, 323, 327, 



351, 356, 370, 408, 609. 

 Tremadoc slates, 163, 192. 

 Trematis, 173, § 203. 



cancellata, 207. 



punctata, 207. 

 Trematodiscus Koninckii, 307,* 



308. 

 Trematosaurus, 428, 429. 

 Trematospira, 171. 

 Tremolite, 54. § 

 Trends, systems of, 29. 

 Trenton epoch, 163,194. 



period, 163, 194, 251. 



period, hornstone of, contain- 

 ing organisms, 261. 

 Tretosternum punctatum, 450. 

 Triacodon aculeatus, 510. 



fallax, 510. 



grandis, 510. 

 Triarthrella, 168, 178. 

 Triarthrus, 204. 



Beckii, 206.* 



range of, in time, 387.* 

 Triassic period, 403. § 



foreign, 423. 

 Triceratium obtusum, 496.* 

 Trichomanites, 271. 

 Triehospongia sericea, 188. 

 Tridymite, 53. § 

 Trigonia, 431, 432, 433, 475. 



aliformis, 476. 



Bronnii, 449. 



caudata, 475. 



clavellata, 438* 449. 



Conradi, 432* 433. 



costata, 449. 



daadalea, 475, 476. 



Evansana, 458. 



gibbosa, 449. 



limbata, 476. 



longa, 476. 



muricata, 449. 



pandicosta, 433. 



scabra, 476. 



Tryoniana, 467- 



vulgaris, 429 



Trigonocarpus, 271, 329, 331, 

 349. 

 ornatus, 329 * 330. 

 tricuspidatus, 329,* 330. 

 Trigonosemus, 171. 

 Trilobites, 122, § 174,§* 180, 

 189, 190, 202, 253, 289, 300, 

 307, 333, 350, 372, 592, 597. 

 a comprehensive type, 382, 



597. 

 culmination of, 249, 594. 

 number of Silurian, 249. 

 range of, in time, 387.* 

 spinous, 285.* 

 Triloculina Josephina, 131.* 

 Trinucleus, 174. § 

 concentricus, 202* 204, 206, 



208. 

 range of, in time, 387.* 

 Trionyx, 509, 510, 519. 



Bakewelli, 450. 

 Triphyllopteris, 348. 

 Tritia trivittata, 510. 

 Triton, 509. 

 Tritonium, 508. 

 Trochoceras, 230. 

 Trochocyathus, 474. 

 conulus, 476. 

 Fittoni, 476. 

 Trocholites, 203.§ 



Ammonius, 205, 201 * 203. 

 Trochonema, 203. 

 Trochosmilia, 474. 

 conoidea, 466. 

 granulifera, 466. 

 striata, 508. 

 sulcata, 476. 

 Texana, 466. 

 Trochus, 475. 



family, 189, 253. 

 Trogon, 516. 

 Trophon antiquum, 519. 

 clathratum, 551, 555. 

 Tropical zone, 609. 

 Tropidoleptus carinatus, 272, 



274. 

 Troxites Germari, 351. 

 Trygon, 263. 



Tsien-tang, eagre of, 661, 666. 

 Tubicinella, 475. 

 Tubicola, 123.§ 

 Tubipora, 620. 



Tufa, 62,§ 66, § 306, 702, 718. 

 Tufa-cones, 706,* 712.* 

 Tulip-tree, 458. 

 Tully limestone, 267. 

 Tunicates. See Ascidians. 

 Tunneling by animals, 608. 

 Tuomey & Holmes, on Pliocene 



of South Carolina, 495. 

 Turbinella Wilsoni, 509. 

 Turbinolia caulifera, 509. 

 Turbo heliciformis, 448. 



subduplicatus, 448. 

 Turf, protection by, 606. 

 Turkey, 511. 

 Turonian group, 470. 

 Turrilites, 462. § 

 Brazoensis, 468. 

 catenatus, 473,* 475. 

 costatus, 476. 

 Oregonensis, 467. 

 polyplocus, 476. 

 Turris, 483. 

 Turritella, 508. 

 alticostata, 495. 

 carinata, 499* 509. 

 Coalvillensis, 508. 

 communis, 519. 



