NORTH PACIFIC OPHIURANS IN NATIONAL MUSEUM CLARK. 121 



W., 391 fathoms, clay, bottom temperature 40.8, 3 specimens. 

 Bathymetrical range, 277 to 685 fathoms. Temperature range, 

 42.2 to 37.9. Fifty-two specimens. 



Type. Cat. No. 25653, U.S.N.M., from station 3071. 



This species is undoubtedly very near the japonica form of aculeata 

 but the character of the disk spines is quite distinctive and the huge 

 radial shields, long arm spines, and peculiar upper arm plates com- 

 bine to give longispina an easily recognizable appearance. Some 

 specimens, however, have the upper arm plates very clearly wider 

 than long and scarcely at all swollen, while the supplementary 

 granules are angular and near together. Such specimens resemble 

 japonica very much, but the character of the disk distinguishes them. 

 The general appearance of this species is remarkably OpMothrix-like, 

 the long arm spines, and finely spiny disk combining with the long, 

 slender arms to make one think of that genus. The geographical, 

 bathymetrical, and temperature ranges of longispina are all remark- 

 ably limited. 



OPHIOPHOLIS BAKERI. 



Ophiopholis bakeri MCCLENDON, Univ. of California Publ., Zool., vol. 6, 1909, no. 

 3, p. 41. 



Disk 10 mm. in diameter; arms about 65 mm. long. Disk plates 

 completely concealed under a dense coat of delicate spines; these 

 spines show great diversity in length, being longest near center of 

 disk and in the interradial areas and shortest on the radial shields; 

 they are more or less thorny and generally end in several teeth. 

 Radial shields entirely concealed, though their outline can often be 

 distinguished, emphasized by the shortness of the spines which cover 

 them. Upper arm plates roundish, sometimes wider than long, often 

 swollen distally; supplementary plates fairly numerous, especially at 

 sides of upper arm plates, but not closely in contact. Interbrachial 

 spaces below covered by a close coat of spines. Oral shields very 

 small, somewhat hexagonal, much wider than long, with long, narrow 

 adoral plates proximal to them. Oral papillae flat and blunt, about 

 three in a group proximal to each adoral plate. Teeth not peculiar. 

 Under arm plates, side arm plates, tentacle pores, and tentacle scales 

 essentially the same as in longispina. Arm spines five to seven; 

 uppermost longest but hardly equal to two joints. Color (dried 

 from alcohol), some shade of pink, ranging from very pale to quite 

 deep, more or less marked and variegated with white. 



Localities. Albatross station 2861, off British Columbia, lat. 

 51 14' N.; long. 129 50' W. ; 204 fathoms, bottom temperature 

 42.6, 1 specimen; station 2866, off Washington, lat. 48 9' N.; long. 

 125 3' W., 171 fathoms, gray sand, bottom temperature 43.2, 



2 specimens; station 2877, off Washington, lat. 48 33' N.; long. 

 124 53' W., 59 fathoms, black sand, mud, bottom temperature 45.5, 



3 specimens; station 2886, off Oregon, lat 43 59' N.; long. 124 56' 



