PART o A MONOGRAPH OF THE EXISTING CRINOIDS 611 



cirrus sockets are arranged in 10 closely crowded columns of from 2 to 4 (usually 3) each; 

 the pairs of columns in each radial area are not separated from those in adjacent radial 

 areas. The apical portion of the centrodorsal bears a number of cylindrical papillae 

 apparently occupying obsolete cirrus sockets. 



The cirri are about XXX, 19-24 (usually 20), the longest 9 mm. long; all the cirri 

 are strongly incurved in the distal half. The first segment is about twice as broad as 

 long, the second is not quite so long as the width of the expanded distal end, the third 

 is somewhat over three times as long as the median width, or twice as long as the width 

 of the expanded distal end, and the fourth, or fourth and fifth, are between five and six 

 times as long as the median width. Those following decrease rather rapidly in length, 

 the last ten or twelve being about as long as broad. The earlier segments have the 

 proximal end slightly expanded and the distal end much expanded and flaring, somewhat 

 more so on the dorsal than on the ventral side, the free edge that overlaps the base of the 

 segment following being finely serrate. The short outer segments are half again as 

 broad distally as proximally. The ventral profile is gently and almost regularly con- 

 cave; the dorsal profile is straight in the proximal half or third, then strongly convex, 

 so that the dorsal distal end is about a third the width of the base of the segment succeed- 

 ing below it. The dorsal extension of the distal ends of the outer segments is rounded 

 and not carinate, and is finely spinous with often a somewhat enlarged central spine. 

 On the outer segments the entire distal edge is produced and overlapping with a glassy 

 border, though this is much less conspicuous in the lateral and ventral portions than 

 dorsally. The opposing spine is long, slender, conical, and erect, terminally situated, 

 reaching a height about equal to the distal width of the penultimate segment and arising 

 from nearly the entire dorsal surface of the segment. The terminal claw is somewhat 

 longer than the penultimate segment and is rather slender and moderately curved. 

 The curious knobby appearance of the cirri in their outer portion is very characteristic. 

 The surface of the cirrus segments is marked with very numerous fine spots. 



The distal border of the radials is just visible beyond the rim of the centrodorsal, 

 from which their outer surface extends outward at right angles to the dorsoventral 

 axis. In the interradial angles the radials are produced distally, separating the bases 

 of the IBri; the laterodistal angles of the radials are separated by a slight notch. The 

 IBri are short, over six tunes as broad as long in the midradial line, slightly longer later- 

 ally then in the midline. They are entirely separated laterally, but their lateral borders 

 are parallel. The dorsal surface is concave. The proximal border is prominent, but 

 smooth. The distal border is slightly produced and finely spinous. The IBr 2 (axillarics) 

 are rhombic, short and broad, half again as broad as long, with the distal edges strongly 

 and the proximal borders less strongly concave. The distal borders are everted and 

 spinous, this spinous eversion having a somewhat stronger curve than the distal edge; 

 the outer portion of the proximal borders bears a few minute spines. The sharp lateral 

 angles of the axillaries are in contact laterally, forming an irregular water pore beneath 

 them. 



The 10 arms are 30 mm. long. The first brachiajs are about three times as long 

 exteriorly as interiorly. From their inner ends the proximal and distal borders run 

 almost parallel to the midline, then diverge rapidly to the outer border. The proximal 

 border is slightly everted but unmodified. The distal border is everted and armed with 

 a frill of webbed spines. The inner ends of two adjacent first brachials diverge at an 



