A MONOGRAPH OF THE EXISTING CRINOIDS 299 



as far as the third brachial are everted and raised, usually broken up into high blunt 

 tubercles which are more or less confluent with similar high and blunt and also more 

 or less confluent tubercles on the dorsal surface. The IIBr and IIIBr series and first 

 two brachials usually have a high and rather narrow median ridge, which is higher 

 than the tubercles on the dorsal surface; this is sometimes partially or entirely broken 

 up into two or three dorsoventrally elongate tubercles which are larger than any 

 others on the ossicles. The proximal edge of the axillaries and the inner proximal 

 edge of the second brachial are curved upward, while the distal lateral angles of the 

 ossicles preceding the axillaries, and the inner distal angle of the first brachial, are cut 

 away leaving prominent openings serving as water pores. The division series are 

 only slightly convex dorsally, and are in very close lateral apposition. 



The 30 arms are 150 mm. long and resemble those of the other forms of the species. 

 The lower brachials to about the fifteenth have strongly everted distal ends which 

 are usually more or less crenulate or tubercular. There is usually a prominent median 

 dorsoventrally elongated tubercle, and usually also some more or less obsolete tubercles 

 on the dorsal surface. From the fifteenth onward the brachials are almost perfectly 

 smooth dorsally. The first sixteen brachials are sharply flattened laterally. 



The pinnules are essentially like those of the other forms. 



The disk is completely covered with a pavement of very small rounded plates. 

 There are well developed side and covering plates along the pinnule ambulacra. 



The color in alcohol is yellowish white, with the calyx, division series, and arm 

 bases as far as the third brachial brownish. 



Notes. A large specimen with the arms about 140 mm. long from Blake station 

 193 differed in so many respects from var. insculpta, (decora), var. gracilis, and var. 

 pulchella (pulchra) that Hartlaub considered it best to regard it as the type of a special 

 variety. 



The centrodorsal, of which the dorsal pole is blackish brown, and the division 

 series and arm bases as far as the third or fourth brachial are dark in color. The arms 

 and cirri are in general lighter, though some arms are dark as far as the middle and 

 beyond. 



In contrast to var. insculpta (decora) the centrodorsal is hemispherical and rather 

 high, and it is further distinguished by prominent interradial ridges and processes. 

 The bare dorsal pole shows a deep, circular, almost black central cavity the edge of 

 which is beset with teeth, which also occur on the first segment of the adjacent cirri. 

 There is no further ornamentation on the centrodorsal. 



Subradial clefts are present. 



The radials are entirely concealed. The whole basal ornamentation, including 

 that of the centrodorsal, entirely lacks the finer protuberances, mostly united into lamel- 

 lae. The ornamentation of the IBr and IIBr series and in part also of the IIIBr 

 series or the first two brachials shows a characteristic feature in that the borders of the 

 individual ossicles are delimited by a row of small light-colored tubercles, resulting in 

 part in a typical dentation. Besides this, there- is on all the ossicles a large median 

 tubercle or median ridge. The lateral borders of the ossicles from the IBr axillaries 

 to the second brachials are somewhat everted and beset with light tubercles, here and 

 there typically dentate; with the exception of the very flat IBr! which is entirely covered 



