PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM nOl 



Hymenodora glacialis G. O. Sars. 



Pasiphae glaciaUs Bnchho\z, Zweite deutsche Nonlpolfahrt, ii, p. 271), pi. I. 



fig. 1, 1874. 

 Hymenodora f/Juciulh G. O. Sars, Arcliiv Mathem. Natiirvid., Kristiana, ii, p. 



341, 1877. Norman, Proc. Royal Soc. Edinburgh, 1881-'82, p. (i84, 1882. 



A few specimeDS from tbe Albatross dredgings of 1883 were doubt- 

 fully referred to this species, but Bucbliolz's erroneous figures and Sars's 

 short diagnosis left the identification so uncertain that I did not men- 

 tion them in the published report. Authentically labeled specimens 

 from the Faroe Channel, recently received from the Kev. A. M Norman, 

 to whose kindness in sending them 1 am greatly indebted, confirm the 

 identification, however, and enable me to positively refer the genus to 

 the Acanthephyrinae and to compare the single species with the closely 

 allied forms, and particularly with my genus Meningodora. 



The eye-stalks aud eyes are very similar to those of Meninqodora mol- 

 lis, but the eyes are apparently a little smaller and are reddish iustead 

 of black in recently preserved alcoholic specimens. 



The mandibles are similar to those of Meningoflora mollis, but still 

 more like those of Acanthephyra Agassizii, the mesial edges being armed 

 very nearly as in that species. The distal segment of the protognath of 

 the first maxilla is very much broader than in Meningodora mollis or any 

 of the species oi Acantheplujra which I have examined, the mesial edge 

 being fully as long as that of the proximal segment, which, however, is 

 considerably narrower raesially than in Meningodora mollis ; the endo- 

 gnath is like that of the Meningodora. The two divisions of the distal 

 segment of the protognath of the second maxilla are nearly equal and 

 much broader and shorter than in Meningodora mollis, and do not i)ro- 

 ject mesially beyond the proximal segment, as they do in. the species of 

 Acanthepliyra, Meningodora, j\^otostomus, and Uphyrina ; otherwise the 

 second maxillae do not differ from those of Meningodora. The maxilli- 

 peds differ essentially from those in the allied genera in having the en- 

 dopod composed of two segments only, a very short proximal segment 

 and a long unsegmented distal one. 



The first gnathopods bear no podobranchiie, and the distal part of 

 the endognath differs from that of Meningodora mollis in having the 

 dactylus nearly as long as broad aud attached to -the propodus by a 

 much less oblique articulation. The number and arrangement of the 

 branchiae and epipods on the succeeding somites are the same as in the 

 allied forms, so that there are in all, on each side, six epipods, six 

 arthrobranchiai, and five pleurobranchia^. The second guathopods and 

 first and second perseopods do not differ essentially from those of Men 

 inogodora mollis, although the second peraeopods are less slender and 

 more like the first than in that species, and both pairs are somewhat 

 more hairy. The third and fourth perjBopods are more like those of 

 Acayithephyra Agassizii than those oi' Meningodora mollis, being armed 

 with small spines and setae, and the proi)odi and dactyli neither grooved 



