42 ART. 2, — H. MATSUMOTO : 



Euryala anopla : Döderlein, Abb. Math.-Phys. Kl. K. Bayer. Akad. 

 Wiss., Suppl.-Bd. I, 1911, p. 98. 



Eastern Sea ; 103-152 fathoms (Clakk). 



Key to Japanese genera of Asteroschematinœ. 



A — Eadial shields entirely covered over ; interbrachial ventral surfaces 

 not so narrowed as to be slit-like ; arm bases strongly ribbed in 



adult specimens ; arm spines not very small Aster oscliema. 



A A — Kadial shields partially naked ; interbrachial ventral surfaces very 

 narrow and slit-like ; arm bases much widened, not strongly ribbed, 

 but almost smooth ; arm spines exceedingly small Astrocharis. 



Key to Japanese species of Asteroscliema, 



A — Disk and arms closely covered with granules . . typical Asteroscliema. 



a — Kadial ribs narrow, not occupying the entire dorsal side of disk ; 

 arms about fourteen times as long as the disk diameter ; three or 

 four granules in 1 mm. on the dorsal side of the arm bases ; oral 

 tentacle pores and some ten &st tentacle pores opening by means 



of tubes tuhi/erum. 



aa — Kadial ribs stout, almost occupying the entire dorsal side of the 

 disk ; five or six granules in 1 mm. on the dorsal side of the arm 

 bases ; oral tentacle pores and only a few first tentacle pores open- 

 ing by means of tubes. 



h — Ventral side of arms closely covered with granules, like the other 



parts ; arms about nine times as long as the disk diameter 



glaucum. 



hb — Ventral side of the arms covered by a skin, which is almost free 

 of granules ; arms about twelve times as long as the disk diameter 



hemigymnum. 



AA — Disk and arms covered by a thick, naked skin, which may, how- 



