172 PROCEEDINGS OF THE ACADEMY OF [April;. 



rather deep sutural channel. This leaves a broad median band in 

 strong relief on the whorls, which have spiral sculpture of spiral 

 cords and threads. The inconspicuous growth-lines arch backward. 



Length 54, diam. 13.8 mm.; 14 whorls. The specimen has lost 

 the last whorl. 



Type No. 3203, A. N. S. P. 



We have not been able to compare the type of Guppy's T. p ani- 

 gyrata, but his description and figure certainly do not support Gabb's 

 identification. Guppy has remarked, however, that his figure of 

 T. planigyrata "shows only the general shape." 



T. sulci gyrata is an abundant species. 



Turritella arata Guppy, in Proc. U. S. Nat. Mus., XIX, p. 319,. 

 PI. 28, fig. 3 from the Oligocene of Haiti, is not contained in the 

 collections studied. 



Caecum anellifer n. n. 



Coecum annulatum Gabb, Trans. Am. Philos. Soc, XV, p. 211 ; Journ. A. N. S. 

 Phila., VIII, p. 363, PI. 46, fig. 59. Not of Brown. 



The single specimen is not mature, but it may be recognized by 

 the sculpture. There are about 25 convex rings, more emphatic 

 posteriorly, lower anteriorly, their intervals much narrower than 

 the ribs, crossed and cut into pits by numerous low axial ribs, which 

 appear very weakly on the rings. Septum rises in a point near the 

 convex side. 



Length 1.95, cUam. 0.6 mm. 



The rings of C. crassicostum Gabb are very much stronger, the 

 intervals wider, so that, with a single example of each at hand, it 

 does not seem prudent to unite them as one species. 



Rissoa epulata n. sp. 



The shell is globose-conic and has a relatively large circular umbili- 

 cus; spire short, straightly conic, of moderately convex whorls, the 

 last whorl inflated. Sculpture of rounded vertical ribs about equal 

 to their intervals, 17 on the last whorl, diminishing and soon dis- 

 appearing after passing over the periphery. In the intercostal 

 intervals there are very low spiral cords, six above the periphery, 

 and the base has four much stronger and more separated cords. 

 A broad and thick varix strengthens the outer lip. The aperture 

 is roundly ovate; peristome continuous. 



Length 1.25, diam. 0.9 mm.; 4f whorls. 



Type No. 3167, A. N. S. P. 



The short form and large umbilicus are the chief characteristics 



