802 



NEW YORK STATE MUSEUM 



Tetragraptus quadribrachiatus, 494^, 49U, 

 499, 504-5, 556, 573, 589, 606, 608, 

 643, 644, 645-47, 649, 655, 657, 744. 

 explanation of plate, 768. 

 figures, 646, 647. 

 serra, 494, 496, 504-5, 530, 548, 556, 573, 

 580, 585, 606, 608, 643, 648, 649, 

 655-57, 744. 

 explanation of plate, 768. 

 figures, 656, C57. 

 Bimilis, 494. 504-5, 550, 573, 643, 

 658-62, 669, 686, 698, 705, 706. 

 explanation of plate, 770. 

 figures, 042, 644, 659, 660, 661. 

 (bigsbyi) similis, 567, 570, 661, 663, 665, 



705. 

 taraxacum sp. nov., 499, 500, 504-5, 530, 

 531, 560, 561, 573, 643. 663-64. 

 explanation of plate, 771. 

 woodi sp. nov., 573, 643. 662-63. 

 explanation of plate, 770. 

 Tetragraptus beds, 639, 651, 659, 673, fol- 

 lowing p.503. 

 Tetragraptus zone, 494-96, 501, 504, 506, 

 508, 540, 636, 646, 647, 648, 660, 664, 665, 

 669, 670, 672, 675, 687, 710, 746, follow- 

 ing p.503. 

 Tetraprionidae, 544, 545, 546. 

 Thamnograptus anna, 591, 627, 629, 630. 

 Theca, first, 484, 520. 

 Thecae, 485; length of, 486. 

 Thuringia, graptolite shales, 471. 

 Tornquist, A., cited, 465, 466. 

 Tornquist, S. L., cited. 460, 462, 463, 464, 

 465, 470, 476, 480, 483, 484, 489, 495, 536, 

 550, 551, 599, 636, 051, 660, 669, 676, 678, 

 679, 680, 681, 687, 695, 696, 704, 710, 734. 



Trenton shales, species from, 467, 739, fol- 

 lowing p.503. 



Triarthrus becki, follotoing p.503. 



Tribes Hill. gra])tolite from, 585. 



Trigonograptus, 499, 508, 539, 545, 550, 

 572, 574, 726-27, 744. 

 sp. ?. 744. 



ensiformis. 499, 506-7, 574, 587, 610, 

 727-29. 

 explanation of plate, 782. 

 lanceolatus, 726, 727. 



Trochograptus, 537, 018. 



Troy, graptolite fauna, folloiving p.503. 



Tullberg, S. A., cited, 462, 463, 470, 488, 

 489, 495. 498, 592, 651, 657, 660, 678, 679, 

 687, 704, 710. 



Ulrich, cited, 493, 503. 



Upper Helderberg group, Dictyonemas in, 



509. 

 Upper Siluric graptolites, 472. 

 Utica shale, graptolite fauna, 467, 468, 



470, 472, 490, following p.503; Diplo- 



graptus, 510; fragments of seaweeds, 



518. 

 T^tica zone, 490. 



Vakkerd, specimens from. 605. 



van Ingen, Gilbert, acknowledgments to, 

 458 ; graptolites photographed by, 481 ; 

 cited, 594, 601. 



Van Schaick island, graptolite fauna, fol- 

 lowing p.503. 



Vanuxem, L., cited, 459. 



Ventral margin, 486. 



Ventral wall, 486. 



Vermont, Dictyonema zone, 493; grapto- 

 lite fauna, 504, 506, 601. 



