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PROCEEDINGS OF THE NATIONAL MUSEUM. 



VOL. 54. 



long and 16/x thick at base. Paired rays slightly curved and 

 strongly divergent, often unequal in length and obtuse at end, 

 200-400;^. long and 20-24/x thick. 



Regular gastral triradiates large. Similar to large dennal tri- 

 radiates. 



Triradiates of oscular margin (g) strongly sagittal. Basal ray 

 straight, nearly uniformly thick for the greater part of its length, 

 sharply pointed, about 300/i, long and 16/x thick at base. Paired rays 



Fig. 7. — Leucandra tuba, a, eegular dermal triradiates. 1), sagittal dermal tri- 



EADIATE. C, TRIRADIATE OF CHAMBER LAYER. d, QUADRIRADIATES OF THE LARGER EX- 

 HALANT CANAL. 6, TRIRADIATE OF THE LARGER EXHALANT CANAL. f, GASTRAL TRIRA- 

 DIATES. fir, TRIRADIATE OF OSCULAR MARGIN. 7t, QUADRIEADIATE OF OSCULAR MARGIN. 

 i, GASTRAL MICROXEA. O— ft, X 100 ; f, X400. 



much shorter and thicker than basal ray; slightly curved, very 

 strongly diverging, about 160/a long and 20/* thick at base. 



Quadriradiates of oscular margin (h) strongly sagittal, exactly 

 similar to triradiates of oscular margin except in having slender 

 apical ray. 



Microxea (^) nearly straight, forming lance-head at one end, 40-56tJL 

 long and 2-4/x thick at head. 



Locality. — Near Olrinoshima, Pro v. Chikuzen in Kiushu (Station 

 4877,59 fathoms). 



