LOWER SILURIC SHALES OF THE MOHAWK VALLEY 123 



found on Snake hill. We figure here two specimens showing addi- 

 tional features. Our species is a very close ally of T. puncto- 

 s t r i a t us Ulrich (title 22, page 685) from the Cincinnati group, 

 with which it has above all the striking surface ornamentation in 

 common. Doctor Ulrich writes me that T. cancellatus has 

 a proportionally greater length and more prominent rostrum. Since 

 T . punctostriatus occurs in the middle beds of the Cincin- 

 nati group it is also considerably younger than the Snake Hill 

 species. 



Miller considered his genus Technophorus as belonging to the 

 lamellibranchs and Ulrich (title 38, page 612) retained the genus in 

 that class, pointing out, however, that in the surface ornamentation 

 and the character of the beaks as they appear in casts of the interior, 

 the genus differs from all known Paleozoic representatives of the 

 class, with the possible exception of Ischyrina Billings. 



The markings are such as to suggest the crustacean nature of 

 Technophorus and the beaks form a single pyramidal prominence 

 instead of two separate points as in lamellibranchs. The Snake Hill 

 species seems to be distinguished from the others by an especially 

 prominent beak (plate 9, figure 18). 



Doctor Clarke in describing a very similar fossil from the Oneonta 

 sandstone (New York State Museum Memoir 6, part 2, 1904, 

 page 406) has stated that he is " more inclined to regard these 

 clavicle-bearing genera (Technophorus and Ischyrina) as bodies like 

 Ribeiria and Ribeirella which Schubert and Waagen have shown to 

 be apodiform crustaceans (Jahrb. der k. k. geol. Reichsanst. 1903, 

 53 : 337)> adding that "it is doubtless true that Technophorus is a 

 ribeirioid crustacean." Doctor Ulrich now also considers these 

 genera as crustaceans. 



