BULLETIN! o'J, UNITED STATES NATIONAL MUSEUM. 

 Measurementg. 



129 



a Specimen broken on one edge, diameter measured along diagonal. 



Specimen No. 8 has a very much excavated base. 



The wall is imperforate. Costse very line and equal in central portion of the 

 base; beyond this area first twelve, then twenty-four, become more prominent than 

 the others; around the edge every fourth costa is more prominent than the interven- 

 ing ones, while there are usually from 12 to 24 that are dominant. The costal 

 margins are entire or microscopically dentate. The outline of the detachment scar 

 is preserved on the smallest specimen. 



The number of septa depends upon the size of the corallum. Specimen No. 9 

 has seven complete cycles, while No. 14 has some mcmhers of the eighth. The first 

 are easily distinguishable b}' being slightly longer than the .second, the second are 

 slightly longer than the third, and the inner ends of the third are more prominent 

 than those of the fourth. At the periphery every fourth septum is approximately 

 equal in prominence, with three decidedly smaller septa between, the penultimate 

 septa being slightly more prominent than the last cycle. The smaller septa are 

 decidedly perforate. The margins oi the large septa may be gently or rather sud- 

 denly arched in the fossular region. \Veak tentacular lol)es are sometimes present. 

 The fossa is moderately elongate. Depth in specimen No. !», 5.5 to (i mm.; in speci- 

 men No. 14, 10.0 mm. The septal dentations are fine, may be sul)microscopic, some- 

 times lacerate. Septal faces minutely and densely granulate; sometimes there are 

 also fine strite. Synapticula rather abundant, not very thick. 



Jjiadh'uK. — S(nith coast of Molokai Island; Station SS4S; depth between 44 and 

 T;i fathoms; temperature of bottom, 67.6 to 71.1 F. (specimens Nos. S-10 of tal)le). 

 Station 3849, depth between 43 and 73 fathoms; temperature of bottom, 67.6'^ F.; 4 

 dead specimens, Nos. 11-14 of tiible, and 13 others, 17 in all. Station 3850, depth 



32301—07 9 



