V °1889"'] PROCEEDINGS OP THE NATIONAL MUSEUM. 351 



ternally grooved longitudinally, with short, even, close-set, slightly 

 spiral grooves. The opening at the distal end is fringed with short, 

 equal papillae, each oue corresponding to the thickened interspace be- 

 tween two of the grooves. These raised folds or interspaces are also 

 finely transversely striate. At the base of the cylinder the epipodium 

 extends backward to the first lateral filament, and the margin of this 

 part is perfectly entire and simple, showing neither fringe nor granu- 

 lation. The object of this apparatus is self-evident. The cylinder 

 serves as a conduit for flic seminal fluid ejected from the verge. Whether 

 it may be employed in an actual copulation is doubtful ; it may merely 

 serve to spread the seminal matter over the eggs as they are deposited 

 by the female. I am not aware that anything of this sort has been ob- 

 served in any other gastropod up to the present time. 



The edge of the mantle is smooth, entire, and slightly thickened. 

 Within the nuchal chamber the anus is visible on the right side. The 

 end of the intestine for a considerable distance is free from the mantle 

 and projects like a tentacle. The termination is slightly constricted, 

 then enlarged into a cup or trumpet-shaped ending, which nearly reaches 

 the mantle-edge. 



The intestine itself, after leaviug the stomach, is much convoluted, 

 but in the main rises and is brought forward nearly to the mantle-edge 

 above the stomach ; then turns back and is carried far into the visceral 

 coil before it is again brought forward and terminated as above de- 

 scribed. The food consists of Foraminifera. 



The gill is free, except at its base, and consists of a very elongate-tri- 

 angular foundation, from which depend triangular lamellae without a 

 raphe and widest at their bases. These grow larger proximally. 



The operculum is thin, polished, amber-colored, centrally depressed, 

 having a central projection or nipple on its under side, and consists of 

 about four whorls. 



The specimen affording the above notes has been identified with .Mr. 

 Watson's type specimen, and is now deposited with it in the British 

 Museum. 



The diagram upon Plate ix (Fig. 3) illustrates the features described, 

 though crudely drawn. The fringe on the left anterior epipodial lappet 

 is too coarse and irregular. The animal is represented as if crawling. 

 The central obliquely lined area represents in section the portion which 

 would extend into the shell, which latter has been omitted to show the 

 parts more clearly. In front on the right, behind the eye, is seen the 

 verge, behind that the distal free end of the intestine. The posterior 

 epipodial filaments may be traced through the operculum. 



This species was obtained by the Challenger off Pernambuco and also 

 in the North Atlantic. It was dredged in some numbers by the Alba- 

 tross at Station 27ii.'5, 125 miles off the coast of the United States, in 

 north latitude 36° 47', in 1685 fathoms. An allied species. 8. Otto'i 

 Philippi, seems to be without this curious sexual modification. 



