Verrill, Notes on liadiata. 297 



A much larger specimen has a test 4-4 inches in diameter, with 

 longest spines 3*5 inches long; anal area 'oS in diameter; genital 

 plates -35 in length, -28 in breadth ; ambulaci-a •45 wide at the 

 periphery. 



In this specimen the amhnlacra are mnch more elevated above the 

 abactinal area and interanibulacra of the npper surface than in the 

 smaller ones. The genital plates are large and acutely triangular, 

 projecting considerably into the iiiterambulacral spaces, forming a 

 well-marked star. The interanibulacra! zones are over five times as 

 wide as the ambulacral at the ])eriphery, where they have ten or tAvelve 

 rows of large tubercles, with a few small tubercles irregularly scat- 

 tered among them. Near the edge of ambulacral zones, on each side, 

 a row of primary tubercles extends upward to the fifth plate from 

 the abactinal area ; between this row and the ambulacra there is a 

 row of smaller alternating tubercles extending a little higher ; and on 

 the other side another similar row of small tubercles extending as 

 far as the genital plates. The next row of primary tubercles attains 

 only to the periphery ; and the third, counting from the ambulacra, 

 terminates two plates below; the fourth extends six plates higher 

 than the third, and considerably beyond the outer arch of the shell ; 

 the fifth ceases two plates earlier than the fourth ; and the sixth one 

 plate sooner, or scarcely above the outer arch, 'J'he median spine- 

 bearing area of the ambulacra has, therefore, a broad petal-like form 

 on the upper surface, reaching about midway to the abactinal area 

 and considerably beyond the foui'th row of primary tubercles, its 

 upper portion including only small scattered tubercles. Its outline 

 is well defined, owing to the contrast between the light yelloAV color 

 of this area, and the deep purplish brown of the naked space above 

 and on each side of its upper portion. The ambulacral tubercles are 

 unequal in size and form tw^o irregular rows. 



The color is nearly like that of the first specimen described, but 

 somewhat darker. The spines of the upper surface are greenish, 

 banded with purple ; below, yellowish or reddish white with few 

 purple bands, or qiiite plain. 



Two specimens in alcohol, intermediate in size between those 

 above described, agree well with the characters indicated. The 

 buccal membrane bears a few very small and slender spines, scattered 

 over the surface and more numerous near the mouth. The spines of 

 the lower surface are all small, slender, rarely exceeding an inch in 

 length, the largest ones enlarged and flattened near the ends, mostly 

 light yellow in color, with faint bands of purple. The long spines are 

 greenish at the base and have narrow bands of bright purple ; the 



