232 



BULLETIN 100, UNITED STATES NATIONAL MUSEUM. 



These stations range in depth from 50 to 554 fathoms (91 to 1,012 

 meters), the average depth being 239 fathoms (437 meters). The 

 average temperature of the stations where this was recorded is 

 51.5° F. (10.8° C). 



Brady records tliis species off the Philippines in 95 fathoms (174 

 meters). 



Cristellaria calcar — Material examined. 



CRISTELLARIA CALCARATA Cushman. 



Plate 45, fig. 3. 

 Cristellaria calcarata Cushman, Proc. U. S. Nat. Mus., vol. 51, 1917, p. 657. 



Description. — Test biconvex, but much compressed, closely coiled, 

 about seven or eight chambers in the last-formed coil; sutures 

 curved, and marked by raised ridges running to the umbonal region, 

 where they unite in a central boss of clear shell material, which is 

 typically excavated in the center, forming a ring of material; per- 

 iphery with a narrow keel from which are rov/el-Iike spines, the two 

 sides often unequal in their angles; apertural face flattened or even 

 concave, aperature radiate. 



Diameter about 2 mm. 



Distribution. — Type specimen (U.S.N.M. No. 9126) from Albatross 

 station D5370, in 159 fathoms (291 meters), off Marinduque Island, 

 bottom temperature 54.3° F. (12.3° C). Besides this station it was 

 found at various stations in the China Sea off southern Luzon; Sogod 

 Bay, southern Leyte; off southeastern Mindoro; off northern Min- 

 danao; and China Sea off Formosa. 



The range of depths of these stations is from 28 to 554 fathoms 

 (51 to 1,012 meters), the average depth 262 fathoms (480 meters). 

 The average bottom temperature where given is 54.1° F. (12.2° C). 



This species is at once distinguished from C. calcar by its orna- 

 mentation, from C. submamilligera hy its spines, and from C. echinata 



