. Alaska. Natural history -- Alaska; Scientific expeditions; Alaska. ii8 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 pedicellarig
. Alaska. Natural history -- Alaska; Scientific expeditions; Alaska. ii8 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 pedicellarige, 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 Fig. 4. Leptastcrias 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 pedicellaria-; fc, double row of interactinal spines with epis;:inai pedicellariae and major pedicellarije 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
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