Tellina.] PELECYPODA. 947 



less distinct ridge from the beaks towards the lower posterior angle ; 

 subequilateral, porcellanous, often elegantly coloured, the periostracum 

 hardly visible ; the umbonal radii internally inconspicuous or absent, 

 the shell-margin entire, the siphonal sinus more or less coalescent 

 below with the pallial line. (Dall.) 

 Inhabiting warmer seas. 



KEY TO SPECIES. 



A. Shell with sharp concentric riblets . . . . . . . . eugonia. 



B. Shell with tine concentric lines. 



a. Adult shell large, solid, beaks slightly anterior or at the middle delloidalix. 

 aa. Adult shell small and thin. 

 b. Anterior end longer. 



c. Shell shortly truncated behind, white . . . . Charlottes, 



cc. Shell wedge-shaped posteriorly, pinkish or yellowish Huttoni. 



bb. Anterior end shorter, both ends convex . . . . urinatoria. 



1. Tellina Charlotte, E. A. Smith. 1885. Plate 54, figs. 11, a, b. 



Tellina (Tellinella) Charlottes, E. A. Smith, Chall. Rep., xiii, 1885, 100, pi. 4, 

 f. 1 ; Index, 91. 



Shell small, thin, compressed, very inequilateral, white ; surface 

 not highly glossy, with a silky, faintly iridescent appearance ; trans- 

 versely elongated, sharply rounded in front, and shortly wedge-shaped 

 behind, terminating in a short truncation. Anterior end considerably 

 longer than the posterior, the dorsal slope slightly excurved, descend- 

 ing only a little ; posterior end with the dorsal margin shorter, very 

 straight and very oblique ; the lower outline slightly arcuate, and 

 very feebly sinuated posteriorly. Sculpture consisting of numerous 

 concentric threadlike lirae, which become gradually thicker as the 

 shell increases. They do not extend quite to the hinder margin, but 

 stop short at a slight fold radiating from the beaks to the lower 

 hindmost extremity. Some of them, however, do reach the margin, 

 and these are elevated into short lamellae, those on the right valve 

 being a little flexuous. Colour white, with the exception of a very 

 faint tinge of yellow towards the beaks. Interior glossy, radiately 

 substriated, with a yellow stain towards the urnbones. Hinge : 

 There are 2 cardinal teeth in the right valve and 1 in the left, that in 

 the latter, and the posterior in the former, being somewhat cleft at 

 the top ; the lateral teeth are slender, elongate, the anterior being 

 rather nearer the beaks than the posterior. Pallial sinus large and 

 deep, extending almost to the front muscular impression. 



Length, 14 mm. ; height, 8-5 mm. ; diameter, 3-5 mm. 



Type in the British Museum. 



Hob. Queen Charlotte Sound, in 10 fathoms ; " Challenger ' : 

 Station 16?A. 



T have not seen this species. 



