A MONOGRAPH OF THE EXISTING CRINOIDS 463 



have prominent dorsal spines; P 2 and P 8 are half again as long as PI, 12-20 mm. long, 

 with 20-26 segments; P 4 is about as long as P 1; or slightly shorter, with 15 segments; 

 the 23-41 arms are 70-125 mm. long. 



Description. The cirri are XVII, 32-36 (the individual cirri counted being 32, 

 33, 34, and 36), and reach 34 mm. in length. The longest cirrus segments are one- 

 third again as long as broad. Short, though prominent, dorsal spines with long 

 bases are developed from the eleventh or twelfth segment onward. 



The radials are scarcely visible. The division series resemble those of Oxymetra 

 finschii. They are in close lateral contact and have straight and sharply flattened 

 sides, which are extended laterally somewhat more than in O.finschii. 



The 40 arms reach a length of 105 mm. 



The proximal pinnules are remarkable for their length, but they are very slender 

 and flagellate. P, is very weak, though long, and is flagellate distally. P 2 reaches a 

 length half again as great as that of PI and has a proportionately more robust base; 

 it reaches almost the same length as P 3 . P 3 reaches 20 mm. in length and is the longest 

 of the proximal pinnules, though it is only very slightly longer than P 2 ; it is composed 

 of 26 segments, which at first are broader than long becoming about as long as broad 

 on the third and about twice as long as broad in the distal portion. P 4 is of about 

 the same length as P! and is of the same stoutness at the base. P 6 is of approximately 

 the same length as P 4 and is much weaker. P 6 is smaller than P 6 . The following 

 pinnules resemble P 4 and are very short. 



Notes. The preceding description was drawn up by the author from the type 

 specimen in the Paris Museum. Muller described this specimen as follows: The 

 40 arms are 100-125 mm. long and very regularly divided. The cirri are XX-XXX, 

 36 40, and cover the centrodorsal with the exception of the middle. Two-thirds of 

 the cirrus segments bear a small spine. There are three radials (that is, the radials 

 are visible and are followed by the two elements of the IBr series), then two ossicles 

 to the next arm division, and beyond this again two ossicles to the succeeding arm 

 division. The axillaries are without a syzygy; they rock to the right and left on the 

 preceding ossicle. The first syzygy is on the third ossicle after the last division (that 

 is, between brachials 3+4), and the distal intersyzygial interval is 12-20 brachials 

 (13-21 muscular articulations). The first pinnule (Pi) is on the second ossicle after 

 the last division. The first pinnule is smaller, the 2 or 3 following large, those suc- 

 ceeding smaller; then" segments are cylindrical and not broadened. The color (in 

 alcohol) is gray-brown. 



Prof. F. Jeffrey Bell described Antedon reginae from Port Molle as follows: The 

 centrodorsal is hidden by the cirri. The cirri are about XXX, 30, about 24 mm. long. 

 The segments are stout and laterally compressed, and about 20 of them are provided 

 with a well-marked spine. The radials are not visible. The IBri are broader than 

 long, and are in lateral contact. The IBr 2 (axillaries) are short, with a very slight 

 backward projection in the middle line. The IIBr series are 2, and the component 

 elements are broad. The IIIBr series are 2. There are 35 arms (the figure shows 38) 

 about 70 mm. long. At first the brachials are fairly regular, though much shorter 

 than broad; later on they become more or less, though never very strikingly, wedge- 

 shaped. If IIIBr series are present there is a syzygy between brachials 3+4. If the 

 arm does not divide a second time there is a syzygy between brachials 5 + 6. There 



