no JOURNAL OF CONCHOLOGY. 



DESCRIPTION OF A NEW SPECIES OF NUCULA, 



AND A LIST OF THE SPECIES BELONGING 



TO THE SUB-GENUS ACILA. 



By EDGAR A. SMITH, F.Z.S. 



(Read before the Conchological Society, Nov. 4, 1S92). 



The very fine species about to be described has recently 

 been obtained by the British Museum from Mr. H. Fulton. It 

 belongs to that section of the genus, characterised by the valves 

 being ornamented with divaricate sculpture, to which Messrs. 

 H. and A. Adams gave the subgenerie name of Acila. Of this 

 group the following recent species are known, and it also occurs 

 fossil in the tertiary formations. 



1. Nucula (Acila) divaricata Hinds. 

 Nucula divaricata Hinds. Zool. Voy. Sulphur, p. 62, pi. 



xviii., fig. 4. 

 N. divaricata Hanley in Sowerby's Thes. Conch, vol. iii., 



p. i55> Pl- 230, fig- 151- 

 N. divaricata Sowerby, Conch. Icon. pi. iv., fig. 29. 

 N. (Acila) divaricata Chenu, Manuel, vol. ii., p. 179, fig. 899. 

 Hab. : China Sea at a depth of 84 fathoms. 



Of this species Mr. Hanley remarks : — "Were it not that 

 the described number of the teeth is much greater in the smaller 

 shell, I should have believed this to be an immature 7niral?ilis" 



2. Nucula (Acila) castrensis Hinds. 

 Nucula castrensis Hinds. Zool. Voy. Sulphur, p. 63, pi. 



xviii., fig. 5. 

 N. castrensis Hanley, Thes. Conch., vol. iii., p. 155, pi. 230, 



fig. 148. 

 N. castrensis Sowerby, Conch. Icon., pi. iv., fig. 32. 



J.C, vii., Oct., 1892. 



