NO VAC ULIXA . 229 



Genus NOVACULINA. 



Novaculina, Benson, Glean. Science, Calcutta, ii, 1830, p. 63. 



TYPE, Novaculina gangetica, Benson ; Rivers Jumna, Gumti, and 

 Ganges. 



Range. Ganges System ; Andaman Islands. 



Original desertion : Shell subiuequivalve, inequilateral, trans- 

 versely elongated; ligament external, communicating with the 

 interior of the shell by an oblique channel. Beaks prominent. 

 Hinge-line nearly straight. Two narrow entering teeth under 

 the beak in one valve, generally three in the other. Syphonal 

 scar very long. Extremities of the shell gaping. Epidermis easily 

 detached when dry, folding over the edges and extremities of 

 the shell, and connecting the hinge-margins. Interior glossy or 

 dull, never pearly. 



Animal. Mantle with the basal-edges united, forming a tube 

 which encloses the animal, longitudinally constricted at the 

 suture. Foot proceeding from the anterior extremity, short, 

 thick, cylindrical, and very muscular ; enlarged at the extremity 

 into a disk, with a convex surface, the plane of which is at right 

 angles with the axis of the foot and shell. Syphons separate, as 

 long as the shell, when fully extended ; the anal one > or that 

 nearest the hinge, half the thickness of the other ; apertures 

 constricted, not ciliated. 



374. Novaculina gangetica, Benson. 



Novaculina gangetica, Benson, Glean. Science, Calcutta, ii (1830, 

 Feb.), p. 63 (as genus Novaculina^ ; A. M. N. H. ser. 3, i, 

 1858, pi. 12 B, fig. 4 ; H. & T., C. I. 1876, p. 47, jl. 116, fig. 7. 



Novaculina novaculina, Gray, A. M. N. H. xiv, 1854, p. 24. 



Solecurtus novaculina, Reeve. Con. Icon. 1874, pi. 7, figs. 31 a& b. 



Tayelus gangeticm, Clessin, in Conch. Cab. 1888, pp. 81-82, pi. 23, 

 fig. 6. 



Original description : Shell oblong, with truncated extremities, 

 white, slightly violaceous internally, epidermis olivaceous. 



The above meagre description was supplemented later * by 

 Benson as follows : " Epidermis easily detached when dry, 

 folding over the edges and extremities of the shell, and con- 

 necting the hinge-margins." 



No measurements being given by the author, the following are 

 taken from three authentic specimens in the British Museum : 



1. 2. 3. 



Long. 9-25 8'75 7 mm. 



L a t 25 20-5 19 mm. 



Diam 6 6 5 mm. 



Hub. Rivers Jumna, Gumti, and Ganges. 



* A. M. N. H. ser. 3, i, 1858, pp. 409-410. 



