Occurrence. Only a solitary female specimen of this form has hitherto 

 come under my notice. It was found in a sample taken at Farsund, south coast 

 of Norway, from moderate depth. 



Amphiaseus denticulatus (Thompson). 



(Suppl. PI. 18). 



Stenhelia denticulata, I. C. Thompson, Revised Report on the Copepoda of Liverpool Bay. 

 Livevp. Biol. Soc. Vol. VII, p. 194, PI. XXX. 



coasi 

 Trans. 



Specific Characters. Female. Body very slender, sub-linear in form, with 

 the anterior division scarcely at all broader than the posterior. Bostrum promi- 

 nent, conically produced. Urosome nearly as long as the anterior division, its 

 segments less sharply marked off from each other than in the 2 preceding species 

 and less coarsely spinulose at the hind edge, last segment well developed, though 

 somewhat shorter than the preceding one. Caudal rami small, broader than they 

 are long and scarcely spinulose at the edges; apical setae quite normal and of 

 moderate length. Anterior antennae rather slender, 8-articulate, 2nd joint the 

 largest, gradually widening distally, and produced at the end outside to an acute 

 spiniform lappet curving anteriorly, 4th joint longer than 3rd, terminal part not 

 attaining the length of those joints combined. Posterior antennae with the middle 

 joint of the outer ramus well defined and setiferous. Oral parts normal. 1st 

 pair of legs slender, with the outer ramus scarcely prehensile, and exceeding 

 somewhat the length of the 1st joint of the inner, its last joint longer than either 

 of the other 2 and narrow oblong in form, being armed with 3 simple spines 

 and 2 slender geniculate setse; inner ramus with the 1st joint linear in form and 

 somewhat exceeding in length the other 2 combined, last joint very narrow and 

 about 3 times as long as the middle one, carrying on the tip a slender claw-like 

 spine, a somewhat longer seta and, inside the latter, a small bristle. Natatory 

 legs with the rami very slender, number of setse somewhat reduced. Last pair 

 of legs with the distal joint rather narrow, conical in form, and edged with 5 

 rather unequal setse, having moreover, just outside the end, a peculiar knob-like 

 appendage tipped by a small hair; inner expansion of proximal joint narrow 

 triangular and scarcely extending beyond the middle of the distal joint, marginal 

 setse 5 in number, none of them of any considerable length. Ovisacs compara- 

 tively small, narrow oblong in form and only containing a limited number of ova. 



Male considerably smaller than female and exhibiting the usual sexual 

 differences. Anterior antennse distinctly hinged and exhibiting the spiniform pro- 

 jection of the 2nd joint characteristic of the species. Inner ramus of 2nd pair 

 of legs biarticulate, with the 2 usual juxtaposed spines outside the distal joint. 



