BULLETIN 59, UNITED STATKS N.VTIONAJ. MUSEUM. 77 



Genus CYATHOCERAS Moseley. 

 CYATHOCERAS DIOMEDEiE, new species. 

 I'lat.' Vll, li-H. I. lr(, 2, 2(1, 2/-. 



Conilluin tall, lower portion ;i thick, elongate, curved or strai<rlit .stalk, rising 

 above an expanded ha.sc, upper portion enlargin<f rapidly. Transverse outline of 

 calice elliptical or oval, usually more or le.ss deformed. 



ME.A.SURKMENTS. 



a Diameters of ealioes measured to outer edge-s of the eost.i-: height mea.sured to upper edges of septa. 



Corallum wall rather thick. Costaj prominent around the calice, corresponding 

 to all .septa except those of the last cycle; in some specimens they may be prominent 

 for some distance below the calice, in others they soon become very low. Low, Hat, 

 or rounded costiB extend to the base. The whole outer surface of the corallum 

 is closely granulated, the granulation on the lower portion usually arranged 

 transversely to the costa'. 



Septa in adult specimens in five complete cycles, or only a few members of 

 the fifth al>sent. The priinaiies and secondaries are of equal .size, extend to the 

 columella, and, except in young individuals, have very cxsert margins; the tcrtiaries 

 are smaller, are not tjuite so long, and lujt so exscrt; the cjuaternaries still smaller, 

 the ([uinaries the smallest, but even these ai'e moderately exsert. The members 

 of the last cycle ai'e nearer to the outer septa of any quarter S3'stem than to the 

 quaternaiy which the\- include, and are partially fu.sed to the sides of the lai-ger 

 septa. Sometimes the margins of the (juaternaries are higher than tho.se of the 

 quinaries, sometimes those of the quinaries ai'e the taller. In young specimens the 

 septa are crowded, in older individuals rather distant. Inner margins of the larger 

 septa transversely undulate. The septal faces show faint striations, with the line 

 of divei'gence at inner edge of wall. The granulations on the faces are not very 

 numerous, usually low and rounded. 



Calicular fossa moderatel}- deep. Columella well developed, large, compressed, 

 prominent, composed of niunerous curled ribbons. 



Local if if's. — South coast of Molokai Island, Station 883."); depth, 169-182 fathoms; 

 bottom, fine brown sand, iiuid; temperature, 55 " F. ; 2 specimens, Nos. 3 and -1 of table. 



Pailolo Chamiel, between Molokai and Maui islands. Station 3868; depth, 127-15'4 

 fathoms; bottom, broken coral, coarse gravel, rock; temperature, 60" to 61" F. ; 1 

 specimen. 



