A MONOGRAPH OF THE EXISTING CRINOIDS 551 



and IIIBr series are thickened and slightly flaring, and there is little indication of 

 synarthrial tubercles; but in the other, while very slight synarthrial tubercles are 

 indicated, the segments are all smooth and indistinct. 



The arms are 40-44 in number, and aie rather more than 100 mm. in length. 

 The brachials soon become very markedly triangular \vith thickened, flaring, and 

 roughened distal edges; but distally they again resume a quadrilateral form and the 

 distal margins are not modified. 



The first syzygy is between brachials 3 + 4, and the second from 8 to 16 brachials 

 beyond. After the second syzygy there may be a second interval of from 8 to 10 

 brachials, but as a rule syzygics become frequent and very regularly spaced, in 1 

 specimen occuning at intervals of 4 and in the other of 5 muscular articulations. 



The pinnules, especially the oral pinnules, are long and slender. Pd is more 

 than 30 mm. in length and consists of more than 70 segments. The succeeding pin- 

 nules decrease in length to P4, which is only about 15 mm. long and is composed of 

 only 20-25 segments. The comb of the lowest pinnules consists of about 12-15 

 segments. The combs persist as far as P4 on which the comb consists of 7 or 8 seg- 

 ments. The basal segments of all the pinnules except at the very tip of the arm are 

 much broader than long. In the basal and middle portions of the arm from 3 to 12 

 of these broadened segments are conspicuous for their flaring spinulose margins which 

 are prolonged on the aboral side into remarkable spinulose spiu-s. These spurs are 

 largest and most fully formed on the basal segments, except the first 2, of the lowest 

 pinnules. Passing distally along the arm as well as outward along each pinnule, 

 these spurs become less and less evident and finally disappear. 



The disk is about 30 mm. in diameter, and is quite fully plated, especially along 

 the ambulacral grooves. The position of the mouth can not be determined. 



The color in alcohol is light brown, the cirri being somewhat lighter than the 

 arms. On drying the color becomes uniformly light fawn or verj^ pale buff. 



Notes. — A specimen from the Gippsland coast may be described as follows: 



The centrodorsal is large, thick discoidal with beveled sides; the dorsal pole is 

 4 mm. in diameter with a pit 1.5 mm. in diameter in the center. The cirrus sockets 

 are arranged in 3 and a partial fourth closely crowded and more or less irregular rows. 



The cirri are very numerous, long and rather stout, XL, 29-30, from 35 to 40 

 mm. long. The first segment is very short, the second is longer, the third is about as 

 long as, or somewhat longer than, broad, and the fifth-seventh or fifth-eighth are the 

 longest, half again as long as broad. The segments following decrease in length 

 so that the tenth or twelfth is about as long as broad and the distal segments are between 

 half again and twice as broad as long. The seventh, eighth, or ninth may be a faintly 

 marked transition segment, though on most cirri no definite transition segment is 

 distinguishable. On the eighth or ninth segment the distal border dorsally is elevated 

 and produced into a broad chisel-Uke edge. In the terminal portion of the cirri this 

 narrows and the last 3 to 6 segments are very bluntly and roundcdly carinate, in 

 lateral view appearing to possess a high carinate dorsal process of which the crest is 

 parallel to the axis of the segment. The opposing spine is low, conical, and much 

 broader at the base than high. The terminal claw is slender, longer than the penulti- 

 mate segment, strongly curved in the basal third but nearly straight in the distal 

 two-tliirds. 



