189 



inferior, its 1st joint ratlier large and tumid, flagellum scarcely twice the 

 length of the peduncle, and composed of about 20 articulations. Inferior 

 antennee but very little longer than the superior, last joint of the peduncle 

 somewhat shorter than the penultimate one. Gnathopoda nearly as in 

 T>. rrythropt:. Last pair of pereiopoda with the po.sterior expansion of the 

 basal joint somewhat smaller and narrower than in the other species, and 

 scarcely reaching beyond the meral joint, its anterior and inferior edges not 

 defined from each other, carpal joint scarcely longer than the meral one, and 

 having anteriorly 3 slender .spines, propodal joint about the same length. 

 Last pair of uropoda with the rami not serrated on their opposite edges, 

 the outer one having only a single dentiform projection anterior to the 

 middle, both rami armed on their upper face with 4 unusually strong denticles. 

 Telson fnlh"- as long as it is broad at the base, outer part considerably 

 tapering, with the tip narrowly rounded, cleft extending nearly to the middle, 

 each of the terminal lobes with a single spinule dorsally. Body highly 

 pellucid, and nearly coloiirless. Length of adult female scarcely ex- 

 ceeding 7 mm. 



BemarJcs. — I think I am right in identifying this form with the 

 B. cntssicornis of Metzger, though neither the description, nor the figures given 

 by that author, are fully satisfactory to distinguish it from its nearest allies. 

 From the 4 species described above, it is easily recognized by the absolute 

 want of any corneal lenses, and from the 2 succeeding species, by the fuller 

 development of the superior antennae. Also the structure of the last pair 

 of pereiopoda and uropoda, and that of the telson, affords rather easily 

 recognizable characteristics. 



Occurrence. — This species has only come under my notice in two localities, 

 viz., at Hvitingso, west coast of Norway, and in the Christianiafjord off 

 Hvalor. Li both places it occurred quite solitary in a depth of from 100 to 

 150 fathoms, muddy bottom. The specimen described by Metzger was taken 

 outside Jaederen, in a depth of 106 fathoms. Out of Norway it has not yet 

 been recorded. 



19. Byblis abyssi, Ci. 0. Sars. 



(PI. 66, fig. 2). 

 Byblis abyssi, G. 0. Sars, Crust. & Pycnogonida nova etc. No. 33. 



Form of body abovrt as in the last species. Cephalon with the frontal 

 part somewhat less produced, and transversely truncated at the tip, lower 

 corners distinct, and nearly right-angled. First pair of coxal plates obliquely 

 expanded distally. Last pair of epimeral plates of metasome obtusely 



