246 

 MOLLUSCA. 



Gasteropoda. 



LoPHospiRA, sp. indet. 



Rainy Island : one very imperfect and badly preserved cast of the 

 interior of the shell of a species of this genus. Limestone rapid, Fawn 

 River : two similar casts. 



EuoMPHALUS, sp. indet. 



Rather large ; much wider than high, outer whorl rounded subquadrate 

 in transverse section ; spire slightly elevated ; umbilicus very wide but 

 shallow. 



Rainy Island : four casts of the interior of a possibly undescribed species 

 of this genus. 



Cephalopoda. 



AcTiNOCEEAS Keewatinense, Whiteaves. 



Plate 30, figs. 7 and 8. 



Actinoceras Keewatinense, Whiteaves. ... 1904. Geol. Svirv. Canada, Ann. Rep., 



vol. XIV, pt. F., p. 54. 



" This is a provisional name for some peculiar, obliquely subnummuloidal 

 and presumably submarginal siphuncles, or portions of siphuncles, some- 

 what resembling those of A. cochleatum (Schlotheim). They are longicone 

 and increase very slowly in thickness, nearly circular in transverse 

 section, and encircled, at more or less regular intervals, by narrow and 

 rather deep, obliquely transverse constrictions. Between these constric- 

 tions the siphuncle is laterally compressed and but slightly expanded, 

 whUe its tranverse diameter is from two to three times as great as the 

 distance between the constrictions. 



" The surface markings of these siphuncles consist of fine, close-set 

 longitudinal striae," and their internal structure is as represented by fig. 

 8 on Plate 30. 



Rainy Island : three fine and rather slender specimens. The best of 

 these, "which shows ten of the siphuncular constrictions, is three inches and 

 nearly a half in length, by twelve millimetres in diameter near the smaller 

 end, and twenty two near the larger. In this specimen the width of the 

 siphuncle is about twice as great as the distances between the constrictions. 

 In another equally slender but shorter specimen from the same locality, 

 which shows seven siphuncular constrictions, the width of the siphuncle 

 is nearly three times as great as the distance between the constrictions, 

 at the smaller end ; and only twice as great as at the larger." Similar 

 specimens have since been found on the Ekwan and Winisk rivers. 



