254 



prominent than in the 2 preceding species, and obtusely acuminate at the tip. 

 Caudal rami somewhat produced, exceeding in length the anal segment, apical 

 setae, on the other hand, unusually short. Anterior antennse of moderate size and 

 distinctly 7-articulate. Posterior antennse, like those in L. Stromi, having the 

 outer ramus quite rudimentary and of conical form, with only 2 hair-like setse. 

 1st pair of legs built on the same type as in the 2 preceding species, though 

 perhaps somewhat less strong. Natatory legs likewise of a rather similar struc- 

 ture, except that the 4th pair is considerably smaller than the others, with no 

 setse on the outer ramus inside. Last pair of legs somewhat resembling in shape 

 those in L. Stromi, innermost seta of the distal joint, however, quite normal, and 

 the 2 outermost setae on the inner expansion of proximal joint both very small. 



Male with the outer rami of 2nd and 3rd pairs of legs much stronger 

 than in female, and having the spines, especially of the terminal joint, very large 

 and divergent; inner ramus of 3rd pair, as in L. Stromi only composed of 2 joints, 

 the distal one produced at the end outside to a short spiniform projection. 4th 

 pair of legs scarcely different from those in female. Last pair of legs much re- 

 duced, distal joint not defined, and replaced by a very slight expansion carrying 

 4 setae, inside which 2 other small setae occur. 



Colour yellowish. 



Length of adult female 0.80 mm. 



Remarks. This form also is closely related to L. Stromi, perhaps still 

 more so than L. curticauda. It is however easily recognised from any of them 

 by the scharply defined body-segments, and more particularly by the unusually 

 short caudal setae, whereas the caudal rami themselves are more produced than 

 in the said species. It seems indeed that the present form has been observed 

 by Prof. Brady, but only regarded by him as a variety of his L. curticauda (= 

 L. Stromi). In PI. 78 of his Monograph 2 figures of a leg of the last pair are 

 given, the one (fig. 7) representing the usual form, the other (fig. 8) indicated as 

 belonging to a variety. The former figure undoubtedly refers to L. Stromi, whereas 

 the latter may have been drawn from a specimen of the present species. The 

 specific name given by Boeck to this species is somewhat inappropriate, as it does 

 not in reality belong to the smaller but rather more to the larger species of 

 the genus. 



Occurrence. I have hitherto only met with this form in the upper part 

 of the Christiania Fjord; but here it occurs at times in great abundance on a 

 muddy bottom, at a depth of 3 to 10 fathoms. 



Distribution. ? British Isles (Brady). 



