A MONOGRAPH OF THE EXISTING CRINOIDS 39 



the elements of the division series, involving all the ossicles from the radials to the 

 first brachials, which as a result have a very serrate appearance. The articulation 

 between the axillaries and the preceding ossicles is sometimes somewhat tubercular. 



There are not more than 20 arms, which are 115 mm. long. The arms are long 

 and slender with a rather smooth dorsal surface and are composed of short brachials. 

 Some arms may arise directly from a IBr axillary. The first brachials are approx- 

 imately rhombic, and are almost entirely united interiorly. The second brachials 

 are of the same size as the first, and are approximately rectangular. The first syzygial 

 pair (composed of brachials 3+4) is squarish, or a little broader than long, and is 

 succeeded by a few discoidal brachials, followed by a short series of triangular brachials, 

 the brachials then becoming blunter and wedge-shaped, and finally more quadrate. 

 The brachials have finely spinous distal ends that project somewhat, slightly over- 

 lapping the brachials succeeding. 



The first syzygy is between brachials 3+4, the second is from between brachials 

 24 + 25 to between brachials 51 + 52, and those following occur at intervals of 10-15 

 (usually 10-11) muscular articulations. In arms arising from a IBr axillary the 

 second syzygy may be between brachials 9+ 10, those succeeding occurring at intervals 

 of at first 3-4 and later 6 muscular articulations. 



PI is mostly only half as long as P 2 , and has relatively smooth segments. P 2 

 is 8-10 mm, long, stouter and stiffer than PI, and is composed of 12-22 segments of 

 which some may be a little longer than broad. The segments have strongly produced 

 dentate distal ends which on the outermost are beset with small spines. P 3 is markedly 

 smaller, and even shorter, than PI. It has smooth segments and agrees entirely with 

 the following genital pinnules. These last increase slowly hi length, reaching 9-10 

 mm. The two first pinnules on the inner side of the arms (P a and P b ) are markedly 

 smaller than the corresponding pinnules on the outer side of the arms (P! and P 2 ). 



The disk is 1 1 mm. in diameter, and is deeply incised. Sacculi are closely crowded 

 on the pinnules, but are more or less concealed by a thick gray -blue layer that covers 

 the perisome and skeleton, and even extends over the small marginal ambulacral 

 lappets of the pinnules, rendering these last unusually conspicuous. 



The skeleton is light gray-blue with small reddish-brown dots. These on the divi- 

 sion series and first 8 or 9 brachials are very numerous and without any definite ar- 

 rangement, but on the outer portions of the arms thay have a regular distribution. 

 Here each brachial has only one spot, which is on its shorter side, lying near the 

 proximal border. The distal pinnules have in part the general gray-blue color, but in 

 part are uniform red-brown, groups of pinnules of the two colors alternating. The 

 cirri are uniform red or golden-brown. 



Hartlaub considered as a variety of Antedon bella, which he called brunnea, a 

 specimen that differed markedly from the typical form hi color as well as in other ways. 



The skeleton is dark brown, the cirri only being light brown. The pinnules have 

 two or three narrow light gray bands. The disk is dark brown with very small white 

 spots. 



There are 19 arms; no postradial series has more than four. The arms are longer 

 and thicker than hi the typical form, the arm length reaching 135 mm. The first 

 syzygial parr (composed of brachials 3 + 4) is quite square. The distal intersyzygial 

 interval in arms arising from a IBr axiliary is 8-9 muscular articulations. The lower 



