OF CONCHOLOGY. 139 



spiniform digitations. Whorls convex or flat between the angle 

 and suture, spirally ribbed, with larger rib-like angular, median, 

 and anterior fascioles (and sometimes post-angular), each emitting 

 long spiniform digitations ; and with a sutural canaliculate 

 digitation accumbent on the spire, continued and recurved back- 

 wards. Cretaceous and Jurassic. 



Typo H. Pelagi. 



Pteroctra Pelagi, d'Orb., Pal. Franc, T. cret. ii, pi. 212. 



CERATOSIPHON, Gill. 



Shell fusi-conic, with the spire considerably elevated, the 

 canal produced into a long digitation recurved towards the left, 

 and the labrum much alated and produced into spiniform digita- 

 tions. Whorls concave or flat betAveen the angle and suture, 

 spirally striated, and with rib-like angular, median, and anterior 

 fascioles, of which the two former, at least, emit spiniform digita- 

 tions, the sutural emitting a digitiform canal accumbent on the 

 spire and directed backwards. 



Type C. MOREAUSIANA. 



Pterocera Moreausiana, d'Orb., Pal. Franc, T. cret. ii, pi. 



211, f. 1. 

 Distinguished by the elongated hamiforra siphonal canal and 

 the posterior canal co-ordinated with the " facies " of Ajwrrhais. 



§ 7. Appendix. 



As the useful " Manuel de Conchyliologie " of Dr. Cbenu is 

 the guide of many conchologists, the species figured therein may 

 be here identified with propriety, especially as some of the 

 species have been misunderstood. Fig. 1612 represents If. 

 rugosa, not "P. chiragy'a "; 1613, '"'• P. lombi's " correctly ; 1614, 

 " P. multipes " = P. violacea correctly ; 1615, P. pseudoscorpio, 

 not "P. Scorpio''; 1616, P. violacea, not "P. millipeda" ; 

 1617, "P. elongatus" ^=^P. elongata correctly. 



