MUSEUM OF COMrARATIVE ZOOLOGY. 313 



Scala Frielei n. a. 



Shell small, thin, whitish, acute at the u[)ex, rapidly enlarging, perforate; 

 spirally .sculi)tur('(l with distinct regularly evenly disposed raised threads 

 without interstitial striu); these are crossed by close-set line incremental lines, 

 and by (in the last whorl about twenty-two) hardly raised, sharp, very thin, 

 irregularly disi)osed lamella?, which are highest near the suture bul not ap- 

 pressed or continuous over it, and are weakest on the peri[)hery; there are 

 three pale smooth polished nuclear, and four ordinary well inllated whorls 

 with a deep but not channelled suture; the base is rounded, the perforation 

 small and oblique; there is no basal disk or cordon; the mouth is rounded 

 oval, with a thin sharp edge; the lamellcc are not crenulated by the spiral 

 lines. Lon. 4.75, lat. 2.5 mm. 



Habitat. Off Hatteras, at Station 2595 in 63 fms., sand, U. S. Fish 

 Commission. 



This pretty species has a good deal the aspect of S. duhia, as figured by 

 Sowerby (Thes., pi. xxxiii. fig. 41), but has a more acute apex and unobstructed 

 suture. It is named in honor of Mr. Herman. Friele of Bergen, distinguished 

 for his excellent researches on the Mollusks of the Norwegian North Atlantic 

 Expedition. The varices hardly rise above the surface, and are extremely thin 

 and sharp. 



Scala Rushii n. s. 



Shell resembling in details of sculpture the preceding species, but yellowish 

 or livid with a pale peripheral zone; shell much more elongated and slender, 

 with three nuclear and six ordinary well rounded whorls ; the twenty-five 

 lamellaj on the last whorl a little more elevated and more regularly disposed, 

 and with a tendency to cross the suture; the base is rounded and imperforate, 

 the mouth rounded oval, the columellar part of the lip alone thickened, the 

 rest sharp, hardly reflected; the sutures are deep and the spiral sculpture very 

 regularly disposed. Lon. 6.25, max. lat. 2.5 mm. 



Habitat. Off Hatteras, U. S. Fish Commission Stations 2595 and 2596, in 

 49 to 63 fms., sand ; and at Samana Bay, St. Domingo, a white, rather more 

 slender variety, stylina. 



This elegant little species is not unlike a S. decussata in miniature, with 

 fainter varices or lamellae, smoother surface, and no basal disk. It is dedicated 

 to Dr. W. H. Rush, U. S. N. 



In the U. S. National Museum there are two species of Scala of this general 

 character, which appear to be nndescribed, but which I reserve for more ma- 

 terial if possible, as they are quite small, and represented by one or two 

 specimens each. 



Scala sericifila n. s. 



Shell slender, solid, pure white, with three translucent apical and six opaque 

 whorls, obtusely angulated at and a little concave behind the periphery. 



