SOME NEW SCYPHOMEDUS.E OF JAPAN. 11 



in their structure, I believe it but proper to range them under 

 the Cepheidse. 



Microstylus, nov. gen. 



Cepheidœ with a four-lobed subgenital cavity and very small 

 appendages among oral frills. Oral arms one-winged. 



Microstylus setouchian us. 

 (Figs. 8-10.) 



Cotylorhiza setouchiana, Kisiuxouye, 1899, in litteris Muh. Zoul. 

 Univ. Tokyoensis. 



Umbrella hood-shaped. Central dome covered with fifty or 



more warts ; separated from the broad brim by a circular groove ; 

 its central portion is generally thin, especially in young specimens. 

 The dome surface with numerous minute brown dots, arranged in 

 radial lines, converging towards the apex of each wart. The 

 umbrella is very thick, but becomes suddenly thin in the brim 

 (fig. 9). 



The umbrella margin is divided into from fifty to sixty 

 lobes, i. <?., each octant of it is furnished with from six to eight 

 oblong velar lobes between every two smaller ocular lobes. 



The straight, uniformly distributed radial muscles seen in 

 the subumbrella gradually become fainter peripherad, finally to 

 disappear altogether before reaching the brim (fig. 10). 



The oral disc is a little depressed and octagonal in shape. 

 From it hang down eight oral arms. On each interradial abaxial 

 side of the disc there is a small round opening communicating 

 with the subgenital cavity (figs. 8, 9). The sides of the disc are 



