540 
E. Verrill — Catalogue of Marine Mollusca. 
TECTIBRANCHIATA. 
Actseon nitidus Verrill, sp. nov. 
Plate LVIII, figure 21. 
Auriculina insculpta Verrill, Proc. Nat. Mus., iii, p. 381, 1880, ( non Mont, sp.) 
Shell small, white, translucent, glossy, elongated, apex obtuse. 
Nuclear whorl rather large, regular. Whorls six, flattened at the 
periphery, gradually increasing, slightly roundly shouldered, sculp- 
ture delicate, wavy, incised spiral lines, more distant and distinct on 
the anterior part of the body-whorl, becoming finer, closer, and more 
wavy behind the middle, obsolete near the suture, except one fine, 
subsutural groove ; suture impressed, or slightly canaliculate. Aper- 
ture narrow-ovate, much contracted posteriorly, a little produced an- 
teriorly ; columella spirally twisted, the inner edge forming a slightly 
raised fold. 
Length, 8 mm ; breadth 3 mm ; length of body-whorl, 5*5 mm ; length of 
aperture, 3‘5 mtn ; its breadth, 1 , 8 mm . 
Stations 892 and 947, in 487 and 312 fathoms, 1880 and 1881, south 
of Martha’s Vineyard. 
The shell formerly recorded as Auriculina insculpta was a young 
dead specimen of this species. 
Ringicula nitida Verrill. 
Ringicula nitida Verrill, Amer. Journ. Sci., Ill, vol. v, p. 16, 1872-3; Verrill, in 
Smith and Harger, Trans. Conu. Acad., iii, p. 48, pi. 1, lig. 2, 1874. 
Dali, Bulletin Mus. Comp. Zool., ix, p. 97, 1881. 
Gulf of Maine, 110 fathoms, “ Bache,” 1872. 
Dredged at ten stations, oft* Martha’s Vineyard, in 1880 and 1881, 
in 100 to 500 fathoms; stations 947, 949, 994, 997, in 100 to 368 
fathoms, 1881. 
Off Florida, 447 fathoms; Gulf of Mexico and Yucatan Straits, 
339 to 640 fathoms (t. Dali). 
Mr. Dali records specimens 7‘5 mm long, 5 mm broad, which is larger 
than any of ours, which seldom exceed 5 mra in length. 
Choristidas, fam. nov. 
The peculiar structure of the following shell, its animal, and the 
radula will not allow it to be placed in any established family. 
Therefore I propose to make it the type of a new family, Choristidce. 
This family may be characterized by the heliciform shell, with the 
perisotraca continuous between the whorls; lip continuous ; columella 
