of extraordinary length. Pleopoda well-developed, with both rami Particulate. 

 Uropoda of moderate •length, and of a similar structure to that in Apseudes. 



Remarks. — This genus has been established by Messrs. Norman &Stebbing, 

 to include some forms differing from Apseudes, among other things, in the absence 

 of the scale-like appendage to the inferior antenna?. As another distinctive 

 character, is mentioned the supposed fusion of the first 2 segments of the meso- 

 some with the cephalon ; but this, I believe, is not quite correct. For in the Nor- 

 wegian species, at any rate, the 2nd segment is well defined from the cephalosome, 

 though apparently rather firmly connected with it. As a third characteristic 

 feature may be mentioned the very pronounced sexual difference occurring in this 

 genus, both as to the general form of the body, and to the structure of the 

 superior antennae and the first 2 pairs of legs. The generic name refers to the 

 peculiar malleolate appearance of the chelipeds, which, especially in the male, is very 

 conspicuous. We know as yet of 4 species, 2 of which, S. malleolus and 8. hides, 

 were procured during the Porcupine Expedition from very considerable depths, 

 the greatest being 1460 fathoms, the 3rd, S. serratus Gr. 0. Sars, likewise from 

 great depths in the Arctic Ocean, the 4th a Norwegian form, to be described below. 



Sphyrapus anomalus, G. 0. Sars. 



(PI. Ill & IV.) 



Apseudes anomalus, G. 0. Sars, TTndersogelser over Christianiafjordens Dybvandsfauna, N. Mag. 



f. Naturvid. f. 1869, p. 45. 



Specific Characters. — Body in female scarcel) r 5 times as long as it is 

 broad, in male considerably more slender. Cephalosome with the upper face 

 evenly vaulted and perfectly smooth, frontal plate broad, rounded, exserted at 

 the end to a short, finely denticulated point. First free segment of mesosome 

 somewhat broader than the cephalosome; the succeeding ones much narrower and 

 defined by deep constrictions; last segment shorter than the others. Metasome 

 perfectly smooth, with the epimera not at all produced, terminal segment occupying 

 about y 3 of the length of the metasome and obtusely rounded at the tip. Superior 

 antennas in female about the length of the cephalosome, 1st joint of the peduncle 

 gradually widening distally, with 4 strong seta? on the outer edge, last joint very 

 small; flagellum scarcely half the length of the peduncle, and 5-articulate, acces- 

 sory appendage about half its length, and 3-articulate; those in male rather 

 larger, flagellum more fully developed, 7-articulate, and carrying dense fascicles 

 of sensory filaments. Inferior antenna? fully as long as the superior, but much 

 narrower, flagellum' much shorter than the peduncle, and 4-articulate. Chelipeds 



