157 



Length of adult female 1.30 mm. 



Remarks. I cannot doubt that the above-described form is that recorded 

 by Thorell as L. furcillatus, though the figure he gives of the female looks 

 somewhat different from that here reproduced. On the other hand the form 

 described (though rather imperfectly) by Brady under that name is certainly 

 very different, and would seem, judging from the figure given of the posterior 

 part of the body in a female specimen, to be more properly referable to the 

 genus Macrocheiron, to be treated of farther on. Though nearly related 

 to the 3 preceding species, the present one may be easily distinguished by 

 the comparatively much shorter caudal rami and the form of the genital and 

 anal segments. The free joint of the last pair of legs also differs conspicu- 

 ously both in shape and armature. 



Occurrence. I have only met with this form in a single locality sit- 

 uated in the upper part of the Christiania Fjord. All the specimens were 

 taken from the branchial cavity of Styela intestinalis. Thorell obtained his 

 specimens from the same Ascidian. 



Distribution. Bohuslan (Thorell), ? Scottish coast (Scott). 



83. Lichomolgus Canui, G. O. Sars, n. sp. 



(PI. LXXXVII). 

 Syn: Lichomolgus albens, Canu (not Thorell). 



Specific Characters. Female. Body of shorter and stouter form than 

 in any of the preceding species, with the anterior division oblong oval in out- 

 line. Cephalic segment not much expanded, being scarcely broader than the 

 succeeding segment, and exhibiting behind a well-marked transverse suture. 

 Tail about equalling in length the cephalic segment, and of a somewhat robust 

 appearance; genital segment rather large and massive, being considerably 

 tumified, with the anterior part slightly marked off from the posterior; anal 

 segment scarcely larger than the preceding one. Caudal rami about twice as 

 long as the anal segment, and somewhat divergent, being of almost equal width 

 throughout; seta of outer edge attached a little beyond the middle; apical 

 setae somewhat resembling those in L. furcillata, being less rudimentary than 

 in the type species. Anterior antennae about the length of the cephalon, and 

 somewhat less slender than in L. albens. Posterior antennae resembling in 

 structure those in the said species, but having the apical claws comparatively 

 longer. Oral parts scarcely differing in structure from those in L. albens. 

 Natatory legs also rather similar; distal joint of inner ramus in 4th pair how- 



21. Crustacea. 



