6 PEOCEEDIlsrGS OF THE NATIONAL MUSEUM vol. 72 



the inner one being much larger than the others, which are almost 

 subeqiial. 



Second maxilla (fig. If) distinctly bilobed at the apex, the inner 

 lobe being somewhat longer and twice as broad as the outer. Both 

 lobes are covered with delicate long and short setae, most of which 

 are arranged in short transverse rows ; they also carry a few stouter 

 setae, two at the inner apex of the outer lobe, and about j&ve at the 

 apex and five at the inner distal margin of the inner lobe. 



Maxillipeds (fig. 1 g), palp with the ischium distinct and armed 

 on the outer side with two short spines. The inner margin of the 

 palp with lobes which bear numerous short and long, stout and fine 

 setae, and the outer margin bearing a few stout setae. The ter- 

 minal part of the palp is distinctly segmented, the segments being 

 mostly marked only through the lobes at the inner and the stout 

 setae at the outer margin. Masticatory lobe narrow, oblong, and 

 ending in a great conical obscurely segmented, densely hairy 

 appendage. 



Legs (fig. 2 a^h) ; in the male the distal joints of the legs are shorter 

 and broader than in the female, and the spines of these joints are 

 arranged in a somewhat different way in the two sexes. The general 

 shape of the joints and also the arrangements of the setae in the 

 males can be best made out from the accompanying figures. 



Pleopoda (fig. 2 c-d) ; in the male the first pleopod has the basal 

 portion large and somewhat expanded laterally. The exopodite is 

 lengthened triangularly, at the middle abruptly narrowing through 

 a break on the lateral margin. The endopodite is two-jointed and 

 slender, the terminal joint being somewhat longer and slenderer 

 than the basal joint, almost linear and rather abruptly narrowing 

 toward the apex. 



The second pleopod has the basal portion much smaller than the 

 first and triangularly produced at the postero-lateral angle. The 

 exopodite is transversely rectangular with the posterior margin 

 concave and the angles rounded. The inner and posterior margins 

 are fringed with very fine short setae and near the inner posterior 

 angle there is also a single stouter seta. The endopodite has the basal 

 joint short and broad, broader at the base, the terminal joint being 

 very long and gradually tapering toward the middle from a rather 

 broad base, then forming a straight needle. 



Remarks. — I have examined a great number of specimens of this 

 species from various parts of south Sweden and find that the first and 

 second pleopoda of the male are subject to a certain variability. 

 Amongst the pleopoda I regard that form as typical which I have 

 described and reproduced above. In rare cases I find, in the first 

 pleopoda, a very short, rounded, heart-shaped exopodite, the back 



