234 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 52 



squarish, the following gradually increasing in length ; third pinnule 

 7 mm. long with about 20 joints, rather stouter than the second; 

 the first three joints are squarish ; fourth pinnule 7 mm. long, with 

 a small genital gland ; following pinnules similar, but with larger 

 genital glands. The distal part of the arms is lacking in all the 

 specimens. 



Color (in spirits). — Brownish yellow, probably yellow in life. 

 Type.— Cat. No. 25452, U. S. N. M., from Albatross Station No. 

 5123; between Marinduque and Mindoro, Philippine Islands; 283 

 fathoms. 



Family PENTAMETROCRINID^ 



Genus PENTAMETROCRINUS A. H. Clark 



PENTAMETROCRINUS DIOMEDE^, new species 



This species is most closely allied to P. atlanticus of Southern 

 Europe and the West Indies ; of the Pacific species it is nearest to 

 P. tuberculatus. 



Centro-dorsal conical, the sides gently convex, 3 mm. high and 

 4 mm. broad at the base, the cirrus sockets closely crowded, arranged 

 roughly in two or three, with sometimes a partial fourth row, and 

 four columns in each radial area. 



Cirri XL-LX_, 14-17 (usually 15-17), 15 mm. to 20 mm. long; first 

 joint short, second squarish, third about twice as long as broad, 

 fourth about three times as long as broad, fifth-seventh about four 

 times as long as broad; following joints gradually decreasing in 

 length, the antepenultimate joint being about twice as long as broad, 

 and the penultimate about as long as broad ; cirri not tapering 

 distally, but the penultimate joint less in diameter than the ante- 

 penultimate ; terminal claw considerably longer than the penultimate 

 joint, stout basally, tapering distally, comparatively straight in the 

 basal half, but curved strongly downward at the tip; cirrus joints 

 practically oblong in lateral view, the distal ventral ends of the more 

 proximal only very slightly prominent ; cirri moderately compressed. 



Arms and pinnules resembling those of P. z'arians, but the lowest 

 pinnule present in that species is absent in P. diomedecc, the first 

 pinnule being on the fifth (epizygal) brachial and bearing a genital 

 gland ; proximal part of the arm moderately tubercular. 



Measurements. — Arms about 100 mm. long; cirri 15 mm. to 20 

 mm. in length. 



Color (in life). — Not distinguishable from P. japonkns. 



Type. — Cat. No. 22699, U. S. N. M., from Albatross Station No. 

 4934; Eastern Sea, off Kagoshima Gulf, Japan; 152-103 fathoms. 



A specimen was obtained at Albatross Station No. 5173; between 

 Mindoro and Luzon. 



