1 18 VERRILL 



dorsal spines are very unequal in size and form. Those on the 

 median radial rows, and in the incomplete, short, intermediate series, 

 are much larger than the rest, about as broad as high, with round 

 capitate tips. They mostly stand singly, but often two to a plate. 

 Large numbers of very much smaller, unequal, minute spinules are 

 thickly scattered over the surface, but not crowded. These stand 

 singly or in small groups on the smaller, intermediate ossicles. Each 

 spine is surrounded by a circle of minor pedicellariae, nearly as large 

 as the smaller spines. These small spines are slender, two or three 

 times as long as thick, terete or slightly clavate, obtuse, partially 

 concealed by the wreaths of pedicellariae. 



X/7 



FIG. 4. 



Leptasterias inequalis V. type, i, Portion of the dorsal surface showing spines of diverse 

 sizes, wreaths of minor pedicellariae, and papular pores. X 17. ii, The same; a, a', adam- 

 bulacral spines and epispinal pedicellariae ; b, double row of interactinal spines with epispinal 

 pedicellariae and major pedicellariae between their bases; c, inferomarginal spines with 

 epispinal pedicellariae. 



The disk is covered with numerous scattered, unequal spines, 

 which do not form very evident circles around the madreporic plate. 

 The latter is small, with fine gyri, and not very far from the center. 



The upper marginal spines are decidedly longer than the median 

 and slightly tapered, obtuse or subacute ; they form a regular single 

 row. 



The inferomarginals and interactinals are a little longer, more 

 slender and less obtuse. The inferomarginals and peractinals each 

 form a single continuous row, the spines becoming shorter and more 

 obtuse distally. The subactinal row extends to about the middle of 

 the ray. The lateral channel between the two marginal rows is 

 narrow but very distinct. 



The adambulacral spines are about as long as the peractinals, and 

 nearly as large. They are terete, often a little thinner in the middle 

 and slightly enlarged toward the obtuse or subacute tips; those 



