430 Dr. J. Gwyn Jeffreys on 



line sharply angular: Jii'nge-j)late broad: teeth strong but 

 short, 8 on the posterior and 6 on the anterior side : inside 

 highly nacreous and glossy, smooth ; inner margin closely 

 and finely notched : muscular scars roundish. L. 0*15. 

 B. 0-175. 



An imperfect specimen and a small valve from Station 7, 

 1100 fms. 'Porcupine' Exp. 1869, off" the north-western 

 coast of Ireland, 420-1470 fms. ' Challenger ' Exp., off" 

 Newfoundland, 1000 fms. 



Allied to N. tuniidula, Malm,=j9?<mi7a (Lov^n, MS.), 

 Asbjornsen, but differs in its smaller size, being more globular 

 and having consequently a less triangular outline, its thinner 

 texture, more prominent and nearly central beaks, and in its 

 finely decussated sculpture. 



Leda pusio, Philippi. 



KiHifla piisiu, Pliil. Moll. Sic. ii. p. 47, tab. xv. fig-. 5. 



Var. latior. Eatlicr larger than the fossil type, but not so 

 solid, more oval than triangular in consequence of the pos- 

 terior side being extended into a beak or point ; agreeing in 

 all other respects with the type. 



Station 9, 1750 fms. ; 12, 1450 fms. 'Porcupine' Exp., 



1869, off" the north-western coast of Ireland, 1180-1215 fms.j 



1870, Bay of Biscay, 257-994 fms. 



Fossil in Calabria (Seguenza). Type from Calabria also 

 (Philippi) ; Messina (Seguenza). 



Leda pustulosa *, Jeff'r. 



Shell forming a short oval, equilateral as regards the 

 position of the beaks, but not as regards the proportions of each 

 side, convex, thin, opaque, glossy, and nacreous : scidpture 

 consisting of slight wrinkled stria?, which radiate from the 

 beaks to the front, and of fine close-set but in*egular concen- 

 tric stride, besides the lines of growth ; there is also a shai-p 

 ridge with a corresponding furrow on the posterior side, 

 causing that last to appear pinched up : colour white, under a 

 pale yellowish-brown ejndermis^ which has a peculiar blistered 

 appearance : margins nearly straight at the back, rounded at 

 the anterior side, sloping at the posterior side to a point some- 

 thing like that of a bill-hook, below Avhich it is indented by 

 the furrow, and curved in front : heal:s central, prominent, and 

 incurved : hnnde inconspicuous : ligament wanting : cartilage 

 and pit minute and narrow: Mnge-Une gently curved: hinge- 

 plate broad, but not thick : teeth small, thorn-like, 12 on each 



• Full of bli.-tei>. 



I 



