KONGL. SV. VET. AKADEMIENS HANDLINGAR. BAND. 22. N:0 7. 367 



carries two laminar appendages. These appendages have been called »dactyloptera» b} 7 

 Spence Bate 1 ) and extend on either side of the dactylus to more than half its length, 

 articulating with the apex of the metacarpus. The hind margin of the dactyloptera is 

 feebly concave, and strongly serrated, the front margin is somewhat curved. The dactylus 

 is scarcely longer than the breadth of the metacarpus and is shorter than a sixth part 

 of its length; at the apex it has a secondary tooth. 



The second pair (PI. XVI, fig. 2) are longer than the first, and reach to the middle 

 of the carpus of the third pair. The femur is straight, linear, and quite as long as the 

 three following joints together. The genu is longer than broad. The tibia is longer 

 than the genu, and is produced at the lower hind corner into a process, which is longer 

 than in the first pair and reaches nearly to the middle of the stem of the carpus; the 

 apex is truncated and serrated as in the first pair. The carpus is like that in the first 

 pair, only a little more elongated; the carpal process does not reach quite to the middle 

 of the metacarpus. The metacarpus and the dactylus are like those in the first pair. 



The third and fourth pairs are similar in shape and equal in length. The femur 

 is narrow and feebly curved, and is a little broader below than above; it is shorter than 

 the three following joints together. The genu is longer than broad. The tibia is about 

 a third part longer than the genu, and has the front margin convex and the hind margin 

 almost straight. The carpus is long and linear, and is considerably longer than the 

 two preceding joints together; the hind margin is fringed with minute spines. The meta- 

 carpus is much narrower than the carpus, curved, and tapering towards the apex, the 

 lower front corner projects into a very short, bluntly triangular process in front of the 

 dactylus. The metacarpus is nearly as long as the carpus. The dactylus is minute, 

 and spine-like. 



The fifth pair (PI. XVI, fig. 3) in the full-grown female reach considerably beyond the 

 apex of the fourth pair. The femur is nearly straight, with the front margin feebly 

 concave and the hind margin feebly convex; just above the lower hind corner projects a 

 strong, more or less sharp-pointed, process; the lower front corner is obtuse; the joint is 

 broader below than above, and is nearly as long as the tibia and the stem of the carpus. 

 The genu is somewhat longer than it is broad below; the lower front corner projects 

 into a more or less sharp-pointed angle. The tibia is more than twice as long as the 

 genu, irregularly pear-shaped, having the base narrowed and the sides bulging. The 

 carpus is elongate, thick and swollen, having the stem about twice as long as broad and 

 the sides somewhat convex; the tubercle on the under margin is large, with the hind 

 margin crenulated, or provided with eight or ten rounded teeth, the incision between the 

 two apical or front crenulations is deeper than between the other crenulations, but not so 

 deep that the tubercle can be properly called two-pointed ; the carpal process is long and 

 curved, evenly tapering towards the apex, more than half as long as the stern of the joint, 

 and much more than twice as long as the tubercle on the under margin of the joint; it 

 is more than two-thirds as long as the metacarpus. The metacarpus is a little shorter 

 than the stem of the carpus, is arched, and has a large, triangular, crenulated tubercle on 



l ) Spence Bate. ' Catalogue of the specimens of Amphipodous Crustacea in the collection of the British 

 Museum, p. 317. 



