CARADOCIAN CYSTIDEA FEOM GIRVAN. 



529 



Strohilocystis, 274, 281. 



Strophomena : grandis. 



strut, Cothurnocystis, 163 ; its function, 234, 244 ; 



C. curvata, 212 ; C. elizae, 174. 

 subvective system, Geratocystis, 258 ; Cheirocrinus 



constrictus ; 324; Cothurnocystis, 169, 226; 



C. curvata, 218; C. elizae, 195-198; Trocho- 



cystis, 250, 252, 253. 

 sugar-loaf plate, Dendrocystis, 74 ; D. harrandei, 



102 ; D. sedywicki, 120. 

 symmetry-plane of Heterostelea, 22, 25. 

 Syringocrhms : paradoxicus. 



tag-process, Cothurnocystis, 164; its function, 235, 



239; 0. curvata, 215; C. elizae, 189. 

 taxonomy of Cystidea, 576, 577. 

 tegmen, Cheirocrinus, 296 ; C. cojistrictus, 323. 

 terminology, 22-25 ; of Pleurocystis, 394. 

 tertius, Homocystitcs, 290. 



Leptocystis, 290. 



Tetracystidae, 264. 



Tetracystis, 264, 281. 



Tetraster : wyville-thomsoni. 



theca, Ceratocystis, 256 ; Cheirocrinus, 291 ; G. 



constrictus, 314; Cothurnocystis, 162-169; 



Dendrocystis, 45 ; D. harrandei, 94 ; D. scotica, 



131; D. sedgwicki, 112; Pleurocystis anglica, 



469, 484 ; P. foriolus, 539 ; P. ^i66a, 524 ; P. 



procera, 490 ; P. quadrata, 505, 518 ; P. rugeri, 



450. 

 thecal openings, Dendrocystis, 76. 

 "thecal ratio," 396 ; Pleurocystis, 552. 

 Thecoidea, 15. 

 Thraive beds, 467. 

 Glen, 4, 128, 171, 209, 311, 339, 487, 502, 



521, 536. 

 Tiaracrinidae, 262, 264. 

 Tirnaskea beds, 467. 

 toe-spine, Cothurnocystis, 164; its function, 235, 



240; G. curvata, 213. 

 tongue-process, Cothurnocystis, 164; its function, 



235, 239; C. curvata, 215; G. elizae., 190. 

 Trautschold, H., 67. 

 Tremadocian, 43, 561. 

 Trenton Falls, 306. 



group, 441. 



Limestone, 42, 157, 406, 411, 417, 422, 429, 



559, 562, 565. 

 Trigtmocystis, 250. 

 trilohatus, Bellerophon, 6. 

 trilobite fauna, Girvan, 560, 568. 

 Trimerocystis, 281, 595. 



Trinucleus : bucklandi, 

 Trinucleus nmdstones, 467. 

 Trochocystidae, 26, 30, 32, 260, 576. 

 Trochocystis, 25, 26, 30, 246, 358, 360, 563, 572, 



592, 593 ; ancestor, 594 : harrandei, hohemica, 



occidentalis. 

 Trochocystitidae, 26 ; see Trochocystidae. 

 Trubin, 41, 92, 109. 

 Trubsko, 41, 90, 93. 

 "tubus ventralis," 67. 

 Tyrone, 7, 466, 468. 



Ulrich, E. O., 565, 566, 615. 

 Upper Lyckholm, see Lyckholm. 

 Upper Mudstones, 6. 



variations, Pleurocystis quadrata, 517. 



"vent," 24; Geratocystis, 258; Cheirocrinus,, 600; 

 G. constrictus, 322 ; Cothurnocystis, 167, 224 ; 

 G. curvata, 219; C. elizae, 199; Dendrocystis, 

 73-75; D. scotica, 141-144; D. sedgwicki, 

 120; Mitrocystis, 249; Pleurocystis, 382; P. 

 anglica, 480; P. quadrata, 514; P. rugeri, 

 459; Trochocystis, 2^Q. 



" ventral," 25. 



Virginia, 37. 



volborthi, Cheirocrinus, 307, 308. 



Glyptocystis, 307. 



" VoUrauten," 301. 



Waagen, W., 615. 



Wachsmuth, C, 155, 615. 



walcotti, Cheirocrinus, 292, 307, 308, 601. 



Wales, N., 7, 447. 



S., 7, 446, 466. 



Warburg, E., 7, 615. 

 Wbller, S., 566, 615. 

 Wesenberg, 288. 



Limestone, 288. 



Weskinde, 35. 

 Westrogothia, 7. 

 Wharfe, Yorksh., 446, 449. 

 Whitehouse group, 4, 568. 

 Wood, Elvira, 300, 615. 

 Woodland Point, 4. 

 Woods, H., 12, 449. 

 Woodward, A. S., 12. 

 wyville-thomsoni, Tetraster, 6, 8. 



Zahorzan, 41, 47, 93, 109. 

 ZiTTEL, K. A. v., 39, 286, 356, 361, 

 615. 



365, 





