185 



15. Byblis longicornis, G. 0. Sars, n. sp. 



(PI. Co, lig. 1). 



Form of body nearly as in B. Guimardii. Cepbalon with the frontal 

 part somewhat less pi'oduced, and nearly transversely truncated at the tip, 

 lower corner well-marked and sliarp. Coxal plates about as in the preced- 

 ing species. Last pair of epimeral plates of metasome obtusely rounded 

 at the lateral corners. First segment of urosome distinctly gibbous at the 

 end dorsally. Corneal lenses somewhat smaller than in the type species, 

 the lower pair placed close to the inferior edge of the cephalon, at some 

 distance from the inferior corners of the front ; ocular pigment well defined, 

 and light brown. Antennae very elongated, the superior ones (in female) much 

 more fully developed than in B. Gnimardii, attaining about V* of the length 

 of the body, peduncle reaching to the end of the penultimate peduncular 

 joint of the inferior ones, flagellum three times as long as the peduncle, and 

 composed of about 35 articulations provided posteriorly with fascicles of 

 slender set*. Inferior antennaj half as long again as the superior, and con- 

 siderably exceeding the length of the whole body, the outer 2 joints of the 

 peduncle nearly equal-sized. G-nathopoda very like in structure those in 

 B. Gdiiiiardii, though the propodos appears somewhat longer in proportion 

 to the carpus. Anterior pairs of pereiopoda with the propodal joint but 

 little longer than the carpal one, dactylus comparatively shorter than in 

 B. Guimardii. The 2 succeeding pairs about as in that species. Last pair 

 of pereiopoda with the posterior expansion of the basal joint densely clothed 

 with setae on the inner face, anterior and inferior edges not distinct from 

 each other, both forming together quite an even curve; carpal joint scarcely 

 as long as the 2 preceding ones combined, and having anteriorly- 5 fascicles 

 of slender spines, propodal joint very slender and exceeding the carpal one in 

 length. Last pair of uropoda somewhat coarser in structure than in the 

 type species, rami lanceolate, with the opposite edges finely serrated, but 

 without any distinct projecting angle al the base, inner ramus with 5 den- 

 ticles inside; penultimate pair with the rami less densely spinous. Telson 

 broader than it is long, oiiter part considerably uaiTowed, with the tip sub- 

 truncated, and bearing 2 slender spines dorsally, cleft very small and narrow. 

 Colour of the living animal not yet stated, but no trace of pigmentary rami- 

 fications present on the cephalon in alcoholic specimens. Length of adult 

 female 12 mm. 



Remarks. — Though very nearly allied to B. Gaimardii, this new 

 species may at once be recognized by the unusually elongated antennae, and 

 especially by the much fuller development of the superior ones. Also the abso- 



24 — Crustacea. 



