518 BULLETIN 82, UNITED STATES NATIONAL MUSEUM 



In one of the 2 specimens from Bock's station 52 the centrodorsal is 10 mm. in 

 diameter at the base. The free dorsal pole is very concave, 6 mm. in diameter. The 

 cirri are arranged in about 3 closely crowded rows. 



The cirri are about LXXV, 30-31, from 29 to 34 mm. long. The dorsal cirri 

 are smaller and shorter, being 25 mm. in length and composed of 26 segments. The 

 first 5 cirrus segments range from broader than long to about as long as broad. The 

 sixth-eleventh or -fourteenth are a little longer than broad. The following segments 

 decrease in length, and are from one-third again to twice as broad as long. From the 

 twentieth or twenty-fifth segment onward there is a very weak and indistinct dorsal 

 spine. The opposing spine is a little stronger than the spines on the preceding seg- 

 ments. The terminal claw is rather stout and is somewhat longer than the pen- 

 ultimate segment. 



The IBri are almost concealed by the centrodorsal. The IBr 2 (axillaries) are 

 low pentagonal, three times as broad as long, with the distal margins concave. The 

 IIBr series are 4 (3 + 4). The IIIBr series are 2. The IVBr series are 4 (3 + 4). The 

 IIBri are interiorly united basally. Both elements of the IIIBr series, and sometimes 

 also the first 2 brachials, are interiorly united. There is a weak synarthrial tubercle 

 on the articulation between the elements of the IIIBr series. The division series are 

 smooth, broad, and tolerably flat. The disk only appears slightly between the inner 

 sides of the IIBr series. 



The 58 arms are 120 mm. long. The brachials are very short, from three to 

 four times as broad as long. The width of the arms in the middle is 2.2 mm. There 

 are 16 brachials for each 10 mm., or 13 if the syzygial pairs are counted as units. All 

 of the arms are grooved. 



Syzygies occur (as an example) between brachials 3 + 4, 16 + 17, and 22 + 23, and 

 distally at intervals of 4 muscular articulations. 



P D is 30 mm. long and is composed of about 60 segments. Its comb is composed 

 of about 20 rather thin and low teeth which rise to a height equal to about half the 

 width of the segments. The teeth extend from the thirty-seventh to the fifty-eighth 

 segment, the terminal segments being without them. The pinnule on the IVBr 

 series, or P 1( is from 22 to 28 mm. long and carries a comb of about 20 teeth. P 2 is 

 about 15 mm. long and has a comb with about 15 teeth. P 3 is 11 mm. long, and its 

 comb has only 6 teeth. If the pinnule on the IVBr series is lacking, there are only 

 4 pinnules (P D to P 3 ) with teeth. P 8 is 9.5 mm. long. The genital pinnules are 14 

 mm. long. The distal pinnules are 11 mm. long with 25 segments, of which the last 

 3 are provided with small dorsal hooks. The proximal pinnules have the first 5-12 

 segments provided with small prominences and are partly webbed with perisome. 

 On about 10 of the posterior arms, from 25 to 30 pairs of pinnules are without 

 ambulacral furrows. 



The disk is 40 mm. in diameter. There are no calcareous granules or papillae. 

 The mouth is marginal and the anal funnel central, 14 mm. high, and sharply set off 

 from the anal interradius. 



The color is brown, with a somewhat lighter median line on the dorsal surface 

 of the arms. 



In the second specimen from Bock's station 52 the dorsal pole of the centro- 

 dorsal is slightly concave, 9 mm. in diameter. 



