GRAPTOLITES OF NEW YORK. PART 1 649 



shoAvn ill the numerous young specimens, which frequently become com- 

 pressed laterally. In this mode of preservation, in T. serra the four 

 branches diverge fully [pl.ll, %.8] ; while in T, amii they coincide more 

 or less [pl.ll, %.7]. 



From T . q u a d r i b r a c h i a t u s , which possesses the same horizontal 

 disposition of tlie branches, this species is readily distinguished by the rapid 

 widening of the branches. 



A feature still more distinctly developed in this species than in the 

 other conveners is the thickness of the dorsal wall of the coenosarcal 

 canal [p.552, pl.ll, fig.5]. 



Tetragraptus fruticosus Hallsp. 



Plato 9, figures 11-14; plate 10, figures 1-10 



Graptolithus fruticosus Hall. Geol. Sur. Can. Rep't for 1857. 1857. 



p.l28 

 G-raptolithus fruticosus Billings. Geol. Sur. Can. Pal. Foss. 1865. 



1:366,375 

 Graptolithus fruticosus Hall. Canadian Organic Remains, decade 2. 1865. 



p.90, pL5, %.6-8 

 Graptolithus fruticosus Hall. N. Y. State Cab. Nat. Hist. 20th An. Rep't. 



1867. pl.3, fig.l5 

 Didymograptus? fruticosus Etheridge jr. Ann. and Mag. Nat. Hist. ser. 4. 



1874. 14:6, pl.3, fig.19 

 Graptolites (Didyniograpsus) fruticosus McCoy. Jour. Geol. Sur. 



Victoria. Prodr. Pal. Yictoria, decade 1. 1874. p.l3, pl.l, fig 9-14 

 Tetragraptus fruticosus Lapworth. Ann. and Mag. Nat. Hist. ser. 5. 1880. 



6:20 

 Tetragraptus (Bryograptus?) fruticosus Brogger. Die sil. Etagen 2 



and 3, etc. 1882. p.39 

 Tetragraptus fruticosus Tullberg. Sver. Geol. Und. 1882. Afh. och 



npps. ser. C, no.50, p.22 

 Tetragraptus fruticosus Lapworth. Roy. Soc. Can. Proc. and Trans. 1886. 



p.l68 

 Tetragrapsus fruticosus Ami. Geol. Sur. Can. Rep't. ser. 2. 1889. v.3, 



pt2, p.ll6k 

 Tetragrapsus fruticosus Gurley. Jour. Geol. 1896. 4:295 



