68 CARL BOVALLIUS, AMPHIPODA HYPERIIDEA. VIBILWM. 



The second pair of antennas (PI. X, fig. 4 and 5) are six-jointed, in the young 

 male, the fifth joint is the shortest. 



The first segment of the pereion is shorter than the second, the fifth is the longest. 



The first pair of pereiopoda (PI. X, fig. 6 and 7) have the carpus considerably 

 shorter than the metacarpus, the posterior margin rounded, armed Avith two strong bristles. 

 The convex anterior margin of the metacarpus is armed with two bristles, the posterior 

 margin is straight, serrated. The dactyl us is longer than half the metacarpus, irregularly 

 serrated along the posterior margin, provided with a distinct aperture at the base as an 

 outlet for the metacarpal glands. 



The second pair (PI. X, fig. 8— 10); the carpus is shorter than the metacarpus; the 

 carpal process is very broad and stout, longer than the carpus itself and quite as long 

 as the posterior margin of the metacarpus. The inner or anterior margins of the process 

 are irregularly serrated (PI. X, fig. 10). The metacarpus is thick, bulging, the anterior and 

 posterior margins convex, the anterior smooth, the posterior regularly serrated. The dac- 

 tyl us is shorter than half the metacarpus, serrated along the posterior margin. 



The third and fourth pairs (PI. X, fig. 11) have the tibia and carpus equal in length; 

 the tibia is tolerably broad but not tumid, the metacarpus is longer than the carpus, the 

 posterior margin smooth. The dactylus is scarcely half as long as the metacarpus. 



The fifth and sixth pairs (PI. X, fig. 12 and 13) are subequal in length, a fourth 

 longer than the fourth pair. The anterior margin of the carpus and metacarpus is armed 

 with a row of very short, equidistant spines. The dactylus is shorter than half the me- 

 tacarpus, armed with some few short spines as in Vibilia gracilis (PI. X, fig. 13). 



The seventh pair are considerably shorter than the fourth; the femur is longer than 

 the three succeeding joints together. 



The pleon is longer than the last four pereional segments. 



The second and third ural segments are coalesced, shorter than the first, and distinctly 

 broader than long. The hinder corners are produced into rounded processes reaching as 

 far backwards as the tip of the telson. 



The uropoda (PL X, fig. 14); the peduncle of the first pair is a little longer than 

 the rami, broader below, distinctly serrated along the outer margin. The interior ramus 

 is scarcely longer than the exterior, both are lanceolate, strongly serrated along the outer 

 margins, and coarsely at the inner. The peduncle of the second pair is as long as the 

 rami, linear, the margins smooth ; the interior ramus is a little broader and longer than 

 the exterior, broadly lanceolate, strongly serrated along both margins; the exterior is strongly 

 serrated along the interior margin and has some few coarse serrations at the outer. The 

 peduncle of the third pair is longer than the rami (7:5), as broad as the peduncle of 

 the preceding pair, and only a little shorter than the last ural segment. The rami are 

 equal in length, the interior minutely serrated along both margins, the exterior smooth 

 along the outer margin and minutely serrated along the inner. 



The telson is almost triangular, as long as broad, and half as long as the peduncle 

 of the last pair of uropoda. 



