238 BULLETIN 100, UNITED STATES NATIONAL MUSEUM. 



Cristellaria expansa, var, planulata — Material examined. 



CRISTELLARIA DENTICULIFERA Cushman. 



Cristellaria cultrata Montfort, dentate variety H. B. Brady, Rep.Voy, Challenger, 



Zoology, vol. 9, 1884, p. 550, pi. 70, figs. 7, 8. 

 Cristellaria dentiadifcra Cushman, Bull. 71, U. S. Nat. Mus., pt. 3, 1913, p. 75, 



pi. 37, fig. 1. 



Description. — Test biconvex, sutures curved; periphery marked by 

 a keel which is denticulate, especially between the terminations of 

 the sutures; the sutures somewhat limbate externally and with 

 raised lines, terminating in a raised mass of clear shell material at 

 the umbo; surface ornamented by a series of broken costae, running 

 longitudinally and somewhat obliquely; especially well-developed on 

 the earlier chambers, becoming obsolete in later growth. 



Diameter up to 2 mm. 



Distribution. — Tjrpical specimens were obtained from Albatross 

 stations: D5110, in 135 fathoms (247 meters), China Sea off southern 

 Luzon, bottom temperature 59° F. (15° C.) ; D5132, in 26 fathoms 

 (48 meters), Sulu Sea off western Mindanao; D5214, in 218 fathoms 

 (399 meters), east of Masbate Island, bottom temperature 51.4° F, 

 (10.8° C.) ; D 5313, in 150 fathoms (270 meters), China Sea off Hong- 

 kong, bottom temperature 53.6'' F. (12° C); D5255, in 100 fathoms 

 (183 meters). Gulf of Davao, D5565, in 243 fathoms (445 meters), 

 between Jolo and Tawi Tawi, bottom temperature 52.3° F. (11.2° C.) ; 

 and D5637, in 700 fathoms (1,280 meters), off Bouro Island. 



Brady records C. cultrata in 95 fathoms off the Philippines, and it 

 would be interesting to know whether this v/as the denticulate form 

 he figures. 



The species is very constant in its characters, and the figures given 

 by Brady in the Challenger Report are good figures of it. 



Cristellaria dentieulifera — Material examined. 



