264 



BULLETIN 75, UNITED STATES NATIONAL MUSEUM. 



Although the general appearance of these specimens is quite dis- 

 tinctive, and trifid stumps appear to be wholly wanting, the indi- 

 cations of a longitudinal white stripe on the upper side of the arms 

 make me suspicious that this is only an extreme variety of koreana. 

 Observations on an extended series of living specimens at Misaki 

 would very easily settle the matter. 



OPHIOTHRIX PANCHYENDYTA, new species.a 



Disk 11 mm. in diameter; arms about 35 to 40 mm. long, probably. 

 Disk thicjdy covered with nearly smooth, cylindrical spines, blunt and 



FIG. 131. OPHIOTHRIX PANCHYENDYTA. a, FROM ABOVE, x 5; 6, FROM BELOW, x 5; c, SIDE VIEW OF 



TWO ARM JOINTS NEAR DISK, X 5; d, AN UPPER ARM PLATE, X 15; e, AN UNDER ARM PLATE, X 15j 

 /, A TENTACLE, X 15. 



rough at tip. Radial shields very large, smooth, nearly free from 

 spines, in contact at inner, distal corner, but elsewhere separated by a 

 narrow series of scales bearing numerous small spines. Upper arm 

 plates (fig. 13ld) rhombic, coarsely granular, a little swollen, wider 

 than long, in contact throughout ; the first one carries a tubercle on 

 which is borne a conspicuous spine. Interbrachial spaces below 

 fully covered with scales and spinelets like those of disk. Oral 

 shields, adoral plates, and under arm plates rather indistinct (as 



u, signifying wholly, and Ivdurbf, signifying clothed, in reference to the inter- 

 brachial spaces below being entirely covered with scales and spinelets.. 



