316 REPORT OF NATIONAL MUSEUM, 1897. 



CRISTELLARIA VARIABILIS Reuss. 

 (Plate 63, fig. 1.) 



Variable in form, according to stage of development, from circular to 

 elongate, compressed; margins generally carinate; young specimens 

 consist of the spiral segments only ; older ones have two or three oblique 

 segments added; walls thin and transparent. Length, about 0.4 mm. 

 (eV inch). 



Localities. Caribbean Sea, North Atlantic, Gulf of Mexico (stations 

 2144, 2263, 2584, 2378, 2394, 2398), 68 to 896 fathoms. 



CRISTELLARIA CREPIDULA Fichtel and Moll. 

 (Plate 63, fig. 2.) 



Elongate or elongate-oval, compressed, smooth, the early spiral ar- 

 rangement of segments soon changing into the linear-oblique; periph- 

 eral margin rounded; sutures slightly depressed. Length, 0.8 to 3 mm. 

 (A to J inch). 



Localities. Off coast of North Carolina, Georgia, Florida, and west 

 coast of Cuba (stations 2614, 2313, 2416, 2641, 2352), 60 to 463 fathoms. 



CRISTELLARIA ACUTAURICULARIS Fichtel and Moll. 

 (Plate 63, fig. 5.) 



Small, ovoid, thick, smooth, with rounded margins; early segments 

 small, closely spiral; later segments increasing rapidly in length and 

 thickness, becoming oblique instead of radial, and somewhat inflated. 

 Length, about 0.6 mm. (-^ inch). 



Localities. Off Carysfort Light, Florida, and off the coast of South 

 Carolina (stations 2641, 2313), 60 to 99 fathoms. 



CRISTELLARIA LATIFRONS Brady. 

 (Plate 63, fig. 3.) 



Elongate, triangular in transverse section, tapering toward each end ; 

 dorsal angle acute and carinate; ventral face broad, flat, or rounded, 

 with acute or rounded marginal angles; early segments closely spiral, 

 later ones growing rapidly longer and more obliquely set, the final one 

 erect and extending nearly the whole length of the shell. Length, 

 1 mm. or less (^ inch). 



Localities. Oft Carysfort Light, Florida, and Gulf of Mexico (stations 

 2641, 2377), 60 to 210 fathoms. 



CRISTELLARIA ITALICA Defrance. 

 (Plate 63, fig. 6.) 



Short and stout, contour in section very nearly an equilateral tri- 

 angle, angles rather sharp, but not carinate; spiral segments rapidly 

 increasing in size, more or less obliquely set; face of the final seg- 



