284 



BULLETIN 100, UNITED STATES NATIONAL MUSEUM. 



smooth; aperture in end view semicircular with a flange-like trun- 

 cated lip. 



Length up to 4 mm. and more. 



Distribution. — ^Type-specimens (U.S.N.M. No. 9146) from Albatross 

 station D5449, in 300 fathoms (549 meters), east coast of Luzon be- 

 tween San Bernardino Strait and San Miguel Bay. It also occurred at 

 D5469, in 500 fathoms (914 meters), in the same region; D5300, in 265 

 fathoms (485 meters), China Sea, vicinity of southern Luzon; and 

 D5236, in 494 fathoms (903 meters). Pacific Ocean, east coast of Min- 

 danao, bottom temperature 41.2° F. (5.1° C). 



This species is nearly four times the size of typical CliilostomeUa 

 ovoidea, and differs in the broadly elliptical outline of the side view, 

 the very thick, opaque test, and in the appearance of the lip, which 

 in direct side view is practically a straight line, while in typical C. 

 ovoidea it is usually a depressed curve. 



Chilostomella grandis — Material examined. 



Genus ALLOMORPHINA Reuss, 1850. 



ALLOMORPmNA TRIGONA Reuss. 



Allomorphina trigona Reuss, Denkschr. Akad. Wiss, Wien, vol. 1, 1850, p. 380, 

 pi, 48, figs. lAa-e. — H. B. Brady, Rep. Voy. Challenger, Zoology, vol. 9, 1884, 

 p. 438, pi. 55, figs. 24-26.— CusHMAN, Bull. 71, U. S. Nat. Mus., pt. 4, 1914, 

 p. 3, pi. 1, figs. 6-8. 



Typical material of this species has occurred at the following six 

 stations: D5112, in 177 fathoms (324 meters), China Sea off southern 

 Luzon, bottom temperature 52.4° F. (] 1.3° C); D5201, in 554 fathoms 

 (1,012 meters), Sogod Bay, southern Leyte, bottom temperature 

 52.8° F. (11.5° C); D5467, in 480 fathoms (878 meters), east coast 

 of Luzon, between San Bernardino Strait and San Miguel Bay; D5529, 

 in 441 fathoms (812 meters), between Siquijor and Bohol Islands, 

 bottom temperature 53° F. (11.7° C); D5625, in 230 fathoms (420 

 meters), between Gillolo and Kayoa Islands; and D5654, in 805 

 fathoms (1,472 meters), Gulf of Boni. 



