Descriptions of New Sj^ecies of Crinoids. 135 



The radials of the second series are ten in number, irregularly 

 quadrangular, lying upon the central upper faces of the first radials, 

 about one half of which they cover. They join, laterally, the third 

 radials, which rest upon them and the extremities of the first radials. 



The radials of the third series are twenty in number, irregularly 

 quadrangular, nearly three times as wide as high. Four of these oc- 

 cupy the space of the upper face of each first radial, two of which rest 

 upon the second radials, and the other two upon these and the extrem- 

 ities of the first radials. 



Azygos piece — Tliis is quadrangular, the inner faces being straight, 

 and meeting the basals in a sharp angle at their line of junction. The 

 lateral faces are convex, and embraced by the concave sides of the first 

 radials. 



Brachials — Of these there are sixty, in series of threes, resting upon 

 the third radials, which they resemble, except that the middle one of 

 each series is slightl}' higher than the others, and bears upon the center 

 of its outer surface a stout, short spine, which is in a line with the 

 center of the brachial and third radial below, and that of the brachial 

 and junction of the double series of arm plates above. 



Arms — Twenty in number, composed of a double row of alternatel}' 

 interlocking pentagonal plates, about forty on each side. These plates 

 shorten and widen gradually towards the extremities of the arms, 

 which are long enough to fold over into the central area of the summit, 

 at the base of the interbrachial rays. They are centrally excavated on 

 the ventral side, and bear two rows of stout pinnuhe. These are few 

 jointed, and excavated like the arms. 



Interbrachial Rays — Five, awl-shaped, thickened and rounded at 

 the base, and gradually tapering to a somewhat blunted point. They 

 are slightly bent downward at the middle, giving the species a pecu- 

 liarly graceful appearance. Their position, and the manner of their 

 articulation to the vault, as well as the description of the latter, may 

 be learned from m}- review of the genus in this Jouknai.^ April, 1879. 



Column. — Small, round, composed of alternately thicker and thinner 

 plates. Columnar canal round. 



Remarks. 



As will be seen from the figures accompanying the description, this 

 species has the body' somewhat depressed, it being but little higher 

 than wide. This form is due mainly to the slender character of the 

 second and third radials, and the brachials. AH the specimens yet 

 found have the top of the vault capped by a Gasteropod. 



