238 BULLETIN '6, UNITED STATES NATIONAL MUSEUM. 



CRYPTOPELTASTER LEPIDONOTUS Fisher. 



PI. 47, figs. 1, 2; pi. 58, figs. 4, 4a; pi. 60, fig. 7. 

 Cryptopekaster lepidorwtus Fisher, Bull. Bur. Fisheries for 1904, vol. 24, June 10, 190.5, p. 311. 



Diagnosis. — Rays five. R=105 mnii,; r=51 mm.; K = 2 (+) r. Breadth 

 of ray at base, between second and third superomarginal, .50 mm. or less, according 

 to degree of inflation of abactinal area. Disk large, rays well developed, tapering 

 to a bkmt recurved tip; interbrachial arcs very wide and rounded; abactinal area 

 much inflated on rays and radial areas of disk, also in each iuterradius adjacent 

 to marginals. Abactinal plates covered with flattened, irregularly quadrate, cir- 

 cular, oval, elHptical, and polygonal granules, with usually more or less projecting, 

 often overlapping, edges. Primary abactinal plates circular or elliptical, well 

 .spaced, with many independent, small intermediate ossicles. Primary plates bear 

 low conical spines or large low bivalved pedicellari^. Marginal and actinal plates 

 completely covered with flat granules; each marginal plate with a single tubercular 

 spine. Ad ambulacra! plates with two thick furrow spines or sometimes a large 

 pedicellaria on the margin, and one similar actinal spine just behind the furrow 

 series. 



Description. — Abactinal surface is covered with peculiar, flattened, scale-like 

 granules, wliich are irregularly quaiirate, circular, oval, elliptical, triangidar, polyg- 

 onal, boomerang-shaped, and of several other shapes wliich defy description, of 

 greatly varying sizes and so closely placed that they often overlap a trifle. They 

 are attached to the larger plates of the skeleton in such a maimer that usually a 

 narrow free projecting edge is discernible, or they form the flaring summit of many 

 variously sized ossicles packed between the regular rows of rather widely separated 

 primary plates. There is some variation in the amount which the edge of the 

 granules extend beyond the attachment area. Overlapping of edges is common. 

 The granules covering the intermediate plates are larger than those surrounding 

 the spines and pediccllarise. 



The exposetl surface of many granules is raised into a low tubercular eminence. 

 Primar}^ plates superficially marked by a robust, low, conical spine, about the base 

 of wliich is a series of elongated granules often curiously excavated on the edge, these 

 spines decreasing in size toward edge of disk and end of ray, and gradmg into broad 

 conical granules in the iiiterradial areas, where the primary plates are small, closely 

 packed, and the secondary ossicles nearly wanting. On the ray is a radial series of 

 spines and on either side three or four parallel series, all low (1.5 mm.), scarcely 

 more than tubercles. Long, low, bivalved pedicellarise (2.5 to 4 mm. in length) are 

 numerous on the abactinal surface, especially on interradial areas, center of disk, 

 and proximal radial areas. Each is surrounded by a series of quadrilateral granules 

 of various sizes; papulae numerous, especially on rays, but apparently absent from 

 a very small intcrrailial area adjacent to marginal plates. 



The abactinal plates when viewed from the inner or ccelomic side are seen to 

 be either circular or elliptical, there being occasionally an indication of one or more 

 short lobes. They are arranged in spaced, not very regular, longituduial series and 

 the interspaces are filled \vitli independent, small, very unequal ossicles, the upper 

 ends of which bear large scale-4ike granules, usually about one (sometimes three or 



