1 82 NEW YORK STATE MUSEUM 



volutions less than two. There is no evidence of spirality in the 

 body whorl beyond the first third of the shell. Section of body whorl 



Platyceras leboutillieri 



circular. Shell growth somewhat irregular in late stages but ap- 

 parently without nodes. 



Aperture but slightly undulated. 



Hight from apex to stoma i8 mm, diameter of body whorl near 

 aperture 14 mm. 



Lower Devonic. Grande Greve and Perce rock, P. Q. 



Platyceras gaspense nov. 



A rather small species with small spiral of one and one half whorls 

 very rapidly expanding so that at the end of the one and one half vo- 

 lutions the shell is of notable width ; thence the whorl becoming free 



Platyceras g a s p e n s e 



and suberect, suggesting the outline of P. t h e t i s Hall of the Ham- 

 ilton shales but with* shorter body whorl and larger spire. The 

 final whorl is compressed but appears to have been subelliptical 

 in cross-section. Surface smooth with one or more longitudinal 

 furrows. 



Middle Devonic. Gaspe Basin, P. Q. 



Platyceras paxillifer nov. 



A small shell closely coiled for two and one half volutions or 

 throughout its length, rapidly expanding and having the general as- 

 pect of a shallow Diaphorostoma or Strophostylus ; the surface 

 roughly corrugated concentrically, the upper shoulder of the shell 

 bearing a single row of slender spines, beginning, in the best pre- 

 served specimens, at the end of the second whorl or the commence- 

 ment of rapid expansion, and three in number at unequal intervals. 

 This species represents one of the large group of spined Platy- 

 cerata so frequent at this period in the development of the genus ; 



