PAL.EOZOIC. 



HYDROZOA. 



CAMBRIAN AND SILURIAN. 



CAMBRIAN. LOWER SIL. 



UPPER SILURIAN. 



•SPECIES. 



Didymograptus (continued). 

 — affinis Nich 



— ancept Xich. 



— argutus Lapw. 



— bifidus Hall 



— caduceus Salt. , 



— crucialis Salt. . 



— divaricatus Mall . 



— elegant Carr. . 



— euodus Lapw. , 



— extensus Hall 



flaccidus Hall 



faseieulatus Nich. . 



furcillatus Lapw., 



geminus His. 



gibberulus Nich. . 



hamatus Baily . 



hirundo Salt. 



indentus Hall . 



— latus M'Coy 



Moffat emit Carr. 



Murchisoni Beck. 



*» 



REFERENCES. 



Didymo. sp. Salt. Q. J. Geol. Soc. vol. xix, p. 137, f. 13 d. 

 D. affinis, Nich. Ann. Mag. Nat. Hist. 4 ser. vol. iv, p. 240, 

 1. 11, f. 20; ib. Hopk. and Lapw. Grapto. of Areuig and 

 Lland. Group, Q. J. Geol. Soc. vol. xxxi, p. 645, t. 33, f . 6. 



Vide Dicellograptus. 



Didymo. Hopk. and Lapw. Grapto. Arenig and Llandeilo, St. 

 David's, Q. J. Geol. Soc. vol. xxxi, p. 646, t. 33, f. 8. 



Graptolithus, Grapto. Quebec Group, p. 73, 1. 1, f. 16-18; 



*■ 3. f- 9" 10 - Nich. Q.J. Geol. Soc. vol. xxiv, p. 136; 



Ann. Mag. Nat. Hist. 4 ser. vol. v, p. 346, f . 7. 

 Vide Tetragraptus bryonoides. 

 Vide Tetragraptus quadri-brachiatus. 

 Vide Dicellograptus Moffatensis. 

 Vide Dicellograptus Morrisii or D. flaccidus, Hall. 



Hopk. and Lapw. Grapto. Arenig and Llandeilo Rocks, St. 

 David's, Q. J. Geol. Soc. vol. xxxi, p. 645, t. 35, f. 1. 



Oraptolithus, Report of Geol. Surv. of Canada, 1857, p. 131 ; 

 id. Hall, Grapto. Quebec Group, p. 80, t. 2, f. 11-16, 1865. 

 Didymograptus, Nich. Ann. Mag. Nat. Hist. 4 ser. vol. v, 

 P- 34 1 . *■ 7> f • 2 ; id. Hopk. and Lapw. Grapto. of Arenig 

 and Llandeilo Group, Q. J. Geol. Soc. vol. xxxi, p. 642, 

 t. 33. f- 1- 



Graptolithus, Grapto. Quebec Group, Supp. p. 143, t. 2, 

 f. 17-19. Didy. Nich. Geol. Mag. vol. iv, p. no, t. 7, f. 

 1-3 ; ib. Ann. Mag. Nat. Hist. 4 ser. vol. v, p. 353, t. 7, f . 6. 

 Leptograp. Lapw. Geol. Mag. vol. x, p. 556. (Nemagraptus.) 



Ann. Mag. Nat. Hist. 4 ser. vol. iv, p. 241, 1. 11, f. 21, 22. 



Grapto. of Arenig and Llandeilo Rocks, St. David's, Q. J. 

 Geol Soc. vol. xxxi, p. 649, t. 35, f. 3. Grapto. geminus, 

 Scharenberg (non His.), Ueber Graptolithen, t. 1, f. I, 3,4. 



Leth. Suec. t. 38, f. 3; ib. Salt. Mem. Geol. Surv. vol. iii, 

 p. 331, 1. 11 B, f. 8 ; ib. Q. J. Geol. Soc. vol. xix, p. 138, 

 woodcut p. 137, f. 13 a. 



Ann. Mag. Nat. Hist. 4 ser. vol. xvi, p. 271, t. 7, f. 3. 



Vide Cyrtograptus. 



Q. J. Geol. Soc. vol. xix, p. 137, f. 13 f ; ib. Salt. Mem. Geol. 

 Surv. vol. iii, p. 331, t. n B, f. 6-8. I), constrictus, Hall, 

 Grapto. Quebec Group, p. 76. D. Geminns, His. Siluria, 

 4 ed. Foss. 9, f. 8, p. 48. p D. patulus, Hall. 



Graptolithus, Grapto. Quebec Group, p. 74, t. 1, f. 20. 

 Didymo. indentus, Hopk. and Lapw. Grapto. Arenig and 

 Llandeilo Rocks, Q. J. Geol. Soc. vol. xxxi, p. 647, t. 33, 

 f . 7 a, c. Var. D. nanus, Lapw. id. t. 33, f . 7 d, and t. 35, 

 f . 4. Didymo. geminus, Nich. (non His.), Q. J. Geol. Soc. 

 vol. xxiv, p. 1 24, t. 5, f . 8, 9 ; ib. Ann. Mag. Nat. Hist. 

 4 ser. vol. v, p. 346, f . 6. 



Graptolithus, Brit. Pal. Foss. p. 4, t. 1 B, f. 7 ; ib. Geinitz, 

 Verst. Grauw. die Grapto. p. 39, t. 2, f. 37, 38. 



Vide Dicellograptus. 



Sil. Syst. p. 694-711, t. 26, f . 4. Prionotus geminus, His. 

 Leth. Suec. Supp. 2, p. 5, t. 38, f. 3. Cladograp. Geinitz, 

 Die Grapto. 1852, p. 30, t. 2, f. 40. Didymo. Baily, Q. J. 

 Roy. Geol. Soc. Dublin, 1861, t. 4, f . 1 ; ib. Salt. Siluria, 

 4 ed. p. 51, Foss. n, f. 13; Foss. 12, p. 61, f. 9, 1. 1, f . 1 ; 

 ib. Hopk. Jour. Queckett Micro. Club, vol. i, t. 8, f . 6 ; ib. 

 Nichol. Ann. Mag. Nat. His. 4 ser. vol. v, p. 349, t. 7, f. 

 7 a, b ; ib. Hopk. and Lapw. Q. J. Geol. Soc. vol. xxxi, 

 p. 648, t. 35, f . 2 a-f . 



