iS 



is a trifle longer than the posterior one, is nearly straight, only a little convex towards the 

 subcentral apex in the largest specimen, more convex in the smaller ones, posterior slope slightly 

 concave, more so just behind the apex, side-slopes nearly straight, except for a more or less 

 pronounced compression, at some distance from the apex. Nucleus compressed, subspiral, smooth. 

 The surface of the shell is covered by regular, very fine, concentric growth-striae and irregular 

 grooves, crossed by faint radiating striae, more conspicuous on the rare spots, where a yellowish 

 epidermis still adheres. Interior of shell porcellaneous. 



Long. 17, lat. 11 1 /.,, alt. 5 Mill. 



In the smaller specimens the posterior slope seems to be shorter, apparently on account 

 of the margin being not intact. 



The species resembles in many respects C. Rathbuni Dall (Proc. U.S. Nat. Mus. 1881, 

 p. 402) figured in the "Blake Gastropoda", PI. 25, figs. 7, ja, but the new species is less depressed 

 and more elongate. C. laevis Thiele (in v. Martens, die beschalten Gastrop. der deutschen Tiefsee- 

 Exp. 1898 — 99, p. 127, PI. 5, fig. 11, 12) is the nearest ally from the Indian Ocean, but is not 

 as broad, and has more regularly curved sides, being probably much less radiately striated. 



The radula has much resemblance with that of C. laevis Thiele, the shape of the 

 rhachidian tooth (R) is really the same, but the upper and side margins are thickened and may 

 be considered as a cusp, the first lateral (1) is much more elongate, not subtriangular, its cusp 

 and that of the second lateral (2) has three denticles, the cusp of the third lateral (3) is simple, 

 the fourth (4) seems to be narrower towards the lower part of the body. The uncini (U) have 

 cusps with a few denticles. The foot has the two epipodial filaments, which characterize the 

 Section Cocculina s. str. of Dall. 



2. Cocculina oblonga n. sp. PI. I, fig. 5; PI. VIII, fig. 9. 



Stat. 126. 3°27'.i N., i25°i8'.7E. 2053 M., hard sand. 2 Spec. 



Shell white under a rather thick epidermis, patelliform, oblong, not much depressed, 

 with a rather acute apex, with curved sides, passing imperceptibly in the regularly rounded ends, 

 which are slightly elevated; anterior slope slightly longer than the posterior one, slightly concave, 

 especially in the lower part, posterior- and side-slopes concave. Apex subcentral, but placed on 

 the posterior half. Nucleus pointed, directed backwards, not spiral, smooth. 



The shell is covered by a very conspicuous, yellowish-brown, fibrous epidermis, which 

 gives to the shell the appearance of being strongly radiately ribbed. Under this epidermis, the 

 shell has numerous concentric and radiating striae, much less conspicuous than those of the 

 epidermis, producing a somewhat cancellated sculpture; interior of shell white. 



Long. 9, lat. 5 x / 4 , alt. 3 Mill. 



The nearest ally seems to be C. radiaia Thiele, of which species I could compare a 

 typical specimen, by the kindness of Dr. MobiuS; this had only a few patches of epidermis, 

 which are however much thinner, yellowish and less fibrous. In C. radiata the front slope is 

 convex, the posterior and side-slopes are also very slightly convex, the front slope is the 

 shortest. The new species is stronger radiately striated, especially on those parts, provided with 



18 



