GRAPrOLITES OF NEW YORK, PART 1 645 



related to S i g m a g r a p t u s p r a e c u r s o r and Coenograptus, though 

 not their progenitor, and, very probably, leading to certain flexuous forms of 

 Didymograptus. 



Tetragraptus quadribrachiatus Hall (sp.) 



Plate U, figure 14 



Graptolithus quadribrachiatus Hall. Geol. Sur. Can. Kep't for 1857. 



1858. p.l25 

 Tetragrapsus crucialis Salter. Quar. Jour. Geol. Soc. 1863. 19:137, 



fig.8b 

 Graptolithus quadribrachiatus Hall. Canadian Organic Remains, decade 2. 



1865. p.91, pl.5, lig.1-5 ; pl.6, fig.5,6 

 Tetragrapsus quadribrachiatus Nicholson. Quar. Jour. Geoh Soc. 1868. 



24:131 

 Gf. Graptolites (Didymograpsus) quadribrachiatus McCoy. Jour. 



Geol. Sur. Victoria. Prodr. Pal. Victoria, decade 1. 1874. p.l5, pl.2, 



fig.l 

 Non Tetragraptus quadribrachiatus Etheridge jr. Ann. and Mag. Nat. 



Hist. ser. 4. 187i. 14:3, pl.3, iig.5-8 

 Tetragrapsus quadribrachiatus Hopkinson & Lapworth. Quar. Jour. 



Geol. Soc. 1875. 31:649, pl.33, iig.9a, 9b 

 Tetragraptus quadribrachiatus Linnarsson. Sver. Geol. Und. 1879. Afh. 



och upps. ser. C, no.31, p.5 

 Tetragraptus quadribrachiatus Brogger. Die sil. Etagen 2 and 3. 1882. 



p.38 

 Tetragraptus quadribrachiatus Tomquist. Sver. Geoh Und. 1883. 



Afh. och upps. ser. C, no.57, p.l6 

 Tetragraptus quadribrachiatus Herrmann. Quar. Jour. Geoh Soc. 1886. 



ser. 3, 3:18 

 Tetragraptus quadribrachiatus Barrois. Ann. de la Soc. Geol. du Nord. 



1892. 20:95 



Tetragraptus quadribrachiatus Matthew. Roy. Soc. Can. Trans, and Proc. 



1893. 11:114 



Tetragraptus quadribrachiatus Gurley. Jour. Geol. 1896. 4:295 

 Tetragraptus quadribrachiatus Roemer & Freoh. Lethaea palaeozoica. 



1897. 1:603 

 Tetragraptus quadribrachiatus Elles. Quar. Jour. Geol. Soc. 1898. 



54:485 



