104 G. F. MATTHEW ON THE 



jectiug- further into the cavity of the valve, due to the cardinal muscle. Several vascular 

 Hues extend forward nearly to the front of the valve. 



Size. Length of the ventral valve 5 mm., width 5^ mm. (The shell is probably 

 somewhat shortened by pressure in the slates.) 



Horizon and Locality. In the dark shales of Division 3a at Navy Island. 



Billings's species was found in the black bituminous limestone, " N," of Table Head 

 (equivalent to the Chazy) Newfoundland ; also in the limestone " P " (equivalent to the 

 Levis) at Portland Creek, Newfoundland. 



PTEROPODA. 



In a previous communication to the Royal Society, the writer remarked upon the 

 peculiar habits of certain shells such as Hyolithes, Cyrtotheca, Diplotheca, and which, 

 though classed as pteropods, had habits differing from the modern pteropods, in that many 

 of them possessed thick shells and dwelt along the shores of the sea. The minute shells 

 described in the following page, however, were of a different kind, and both in size and 

 aspect, as well as association, appear to fall within the Pteropoda. 



STYLIOLA, Lesueur. 



This name given by Lesueur, has been applied by Barraude and others to a group of 

 minute pteropods found in the Upper Silurian and the Devonian rocks. So far as I am 

 aware, they have not been reported from earliar palœozoic strata or from the mesozoic 

 rocks, and the modern forms referred to the genus are said by Zittel to be distinguished 

 by their larger size and by other features. The fauna associated with the three following 

 species, as well as the attitudes in which they occur in the shales, seems to indicate 

 somewhat clearly that they are veritable oceanic forms. 



Styliola. prim^va, n. sp. (PI. VII., figs. 10a and b.) 



Nat. Hist. Soc. of N.B., Bulletin x., p. viii. 



A minute slender cone, apparently smooth, eight times as long as wide. 



Size. Length about 3 mm. 



Horizon and LocalHy. In black graphitic shales of Division M at the Suspension 

 Bridge. Abundant on certain layers with Didymogr aphis nilidus and D. patulus. 



This species is referred to Styliola rather than Tentaculites because no annulations 

 could be detected. The shell is squeezed flat between the layers, but if annulations had 

 existed, some traces of them should still be visible, as the corrugations on the surface of 

 the associated species are sufficiently distinct. 



CRESEIS, Rank. 



Associated with the preceding are some larger pteropods which it at first appeared 

 might be included in Salter's genus Cyrtotheca, but an examination of the species included 

 under that genus shows that they belong to the larger type of pteropods of the palaeozoic 

 rocks (Hyolithes, etc.) The St John species described below, however, are so clearly of type 

 of the small pelagic pteropods that it seems proper to place them under the above designa- 

 tion. It is acknowledged that the above genus is a synonym for Styliola but some writers 



