72 CARL BOVALLIUS, AMPHIPODA HYPERIIDEA. VIBILID^. 



The first pair of pereiopoda have the carpus as long as the metacarpus; the posterior 

 margin is straight without bristles. The anterior convex margin of the metacarpus is smooth, 

 the posterior margin is straight, finely serrated. The dactylus is shorter than half the 

 metacarpus, finely serrated at the posterior margin. 



The second pair (PI. X, fig. 24) have the carpus longer than the metacarpus; the 

 carpal process short, indistinctly serrated, shorter than half the posterior margin of the 

 metacarpus. The anterior and posterior margins of the metacarpus are convex, the poste- 

 rior regularly serrated. The dactylns is shorter than a third of the metacarpus, not serrated. 



The third and fourth pairs (PI. X, fig. 25) are very robust, the tibia and carpns 

 are very broad, almost tumid, the posterior margins straight, beset with very few minute 

 spines. The metacarpus is shorter than the carpus, finely serrated along the posterior 

 margin. The dactylus is shorter than half the metacarpus. 



The fifth and sixth pairs (PI. X, fig. 26) are a third longer than the fourth pair, 

 robust. The carpus is longer than the tibia, minutely serrated along the anterior margin. 

 The metacarpus is feebly bent, fringed along the anterior margins with minute spines. 

 The dactylus is scarcely more than a fifth of the length of the metacarpus. 



The seventh pair equal two thirds of the fourth pair in length; the femur is 

 longer than the three succeeding joints together. 



The pleon is as long as the last five pereional segments; the lower margins of the 

 segments are feebly rounded. 



The pleopoda, have the peduncles longer than the rami. 



The second and third ural segments are only partly coalesced, the distinction between 

 both the segments being marked at the sides by deep incisions or notches. The coalesced 

 segment is as long as the preceding first ural segment. The hinder corners are produced 

 backwards into obtuse processes, not reaching as far as the hinder margin of the telson. 



The uropoda (PI. X, fig. 27 — 30); the peduncle of the first pair is much longer 

 than the rami, broader below, complicated serrated along the outer margin; the rami are 

 lanceolate, equal in length, showing peculiar apertures at the under-side and well-developed 

 glands in the interior 1 ). The exterior ramus is strongly serrated along the outer margin, 

 and coarsely along the inner. The interior ramus is sharply serrated along both margins 

 with some few coarse teeth at the lower end. The peduncle of the second pair is much 

 longer than the rami, a little broader below, indistinctly serrated along the outer margin. 

 The rami are almost equal in length; the exterior sharply serrated along the inner margin 

 and coarsely along the outer; the interior ramus is sharply serrated along both margins, 

 The peduncle of the third pair is pear-shaped, very short, shorter than the rami and half 

 as long as the last, coalesced ural segment. The rami are equal in length, tolerably 

 broad. The exterior ramus is almost smooth along the outer margin and sharply serrated 

 along the inner margin with a very large aperture at the lower end; the interior ramus 

 is sharply serrated along both margins. 



The telson is broadly rounded, almost broader than long and somewhat longer than 

 the peduncle of the last pair of uropoda. 



') This peculiar organ will be spoken of in the anatomical part of the treatise. 



