J.VTANESE ASTEROIDEA. 655 



membrane, and in alcoliolic specimens are more difficult to count 

 than those of the first series. 



Mouth-plates. — Each mouth-plate bears on tlie furrow margin 

 6-7 spines, of wliich the first two or three, are conspicuously 

 larger than the ada,ml)ulacral spines and the rest nearly equal to 

 tlie latter, the length gradually decreasing away from the mouth. 

 On the actinal face of the plates there is a group of spines, 

 which are sometimes arranged in a curved line parallel to the first 

 series of spines, but sometimes more like those of the ventrolateral 

 plates. "When they are arranged parallel to the first series, there 

 are usually 4 or 5 larger and a few smaller spines for each 

 mouth-plate ; in the other case the number of spines remain near- 

 ly the same, only the arrangement being different (PI. XIX, fig. 

 277). 



Ventrolaterals. — The ventrolateral plates are all small, but 

 are largest along the ambulacral furrow and gradually decrease 

 towards the margin, where thev are bounded bv the series of 

 larger plates already mentioned. The plates are regularly arrang- 

 ed in rows parallel to the ambulacral furrow, so that those belong- 

 ing to any two adjacent arms together form a V-shape ; about ten 

 of these V-shaped series can be counted in each interradius. It is 

 very difficult to count the spines on each plate in alcohohc 

 specimens, as they are covered over for the most part by a 

 tumid membrane, but in dried specimens they are very distinct 

 though small, and each plate bears G-10 of them, except on the 

 very small plates near the margin which may bear less. 



Dorsal plates. — On the sides of the arms the dorsal plates 

 are distinctly arranged in longitudinal rows parallel to the length 

 of the arms, so that the rows of the adjacent arms form about 



