252 PATELLID.E. 



A. Adams. It depends on concliological characters. 

 The apex of the shell turns backwards^ instead of for- 

 wards or towards the head, which latter is the case with 

 Tectura and the other preceding genera of the same 

 family. The animal is blind, an infirmity that it shares 

 with T.falva and the succeeding genus Propilidium. 



Lepeta c^ca^_, Miiller. 



Patella cceca, Mull. Prod. Z. D. p 237. 



Body whitish : tentacles setose : foot large : liver green 

 (Miiller and Stimj)son). 



Shell having an oval outhne, moderately solid, opaque, 

 sUghtly glossy : sculpture, very numerous and close-set fine 

 s'triae, which radiate from the beak, and are crossed by shghter 

 concentric and imbricated striae, the intersection of which 

 causes the longitudinal striae to be granular or nodulous, 

 especially towards the margin; marks of growth distinct: 

 colour milk-white : heaJc blunt, much worn in full-grown 

 specimens : mouth oval : margin thin and even, minutely 

 tiiberculated in immature specimens : inside porcelain-white, 

 aind partly iridescent : central scar large and conspicuous : 

 pallial scar rather broad and glossy, placed between the central 

 scar and the margin. L. 0*5. B. 0*35. 



Habitat : Off Unst, in Shetland, at a depth of from 

 80 to 90 f., — Mr. Dawsori having found a fine and 

 fresh but somewhat broken specimen in sand which I 

 dredged there last summer. I should not be so well 

 satisfied of this evidence that it is British, if it had not 

 been confirmed by my discovering a smaller specimen 

 (having the dried remains of the animal in it) among 

 some of Tectura fulva which Mr. Barlee dredged on the 

 west coast of Scotland in 1846. He was never, as I 

 believe, acquainted with this species, nor had any shells 

 from Scandina^da, where it is rather commoii. I may 

 * Bhnd. 



