288 CAEL BOVALLIUS, AMPHIPODA HYPERIIDEA. I. 2. HYPERIIDiE. 



Euthemisto libellula. 



The metacarpus is a little shorter than the carpus; the front margin is convex, and 

 fringed with bristles; the hind margin is almost straight, finely pectinated, with long, spine- 

 like teeth, and is bordered with bristles. The dactylus is strongly curved, and is finely 

 serrated at the base on the hind margin; it is not half as long as the metacarpus. Glands 

 are developed in all the joints, except the dactylus. 



The second pair reach fully to the apex of the third. The femur is nearly linear, 

 longer than the three following joints, and has the margins smooth. The genu is broader 

 than long, with long bristles at the lower hind corner. The tibia has the hind part 

 strongly produced, forming a tongue-shaped process, feebly angular at the apex, and 

 reaching almost as far as to the base of the metacarpus; the margins of the process are 

 densely fringed with long, slender bristles. The carpus is only a little dilated; the front 

 margin is feebly curved, and is set with long bristles, the hind margin is smooth; the 

 carpal process is very long and narrow, and is nearly as long as the stem of the joint ; the 

 front side is narrowly gouge-shaped, with the margins set with equidistant, spine-like 

 bristles; the apical spine is stout but short, and scarcely a sixth part as long as the process 

 itself. The metacarpus is as long as the stem of the carpus, and a little longer than 

 the front. side of the carpal process; the front margin is convex, and fringed with long 

 bristles; the hind margin is straight, and pectinated, with long, spine-like teeth. The dac- 

 tylus is like that in the first pair, the glandular opening at the base is unusually large; 

 the dactylus is not fully half as long as the metacarpus. 



The third and fourth pairs (PI. XIII, fig. 24) are tolerably similar in form but 

 unequal in length, the fourth being much the longer. The femur is broad, about twice 

 as long as broad, with the hind margin strongly convex and the front margin irregularly 

 concave, each provided with four or six spines near the apex. The genu is longer than 

 broad, and has two or three short bristles on the hind margin. The tibia is longer than 

 the genu; the lower front corner is produced, and armed with three or four spines; the 

 hind margin is armed with four or five spines, and shows between the spines a fringe of 

 soft hairs, which often are curved at the apex. The carpus is ovate, with a deep incision 

 on the hind margin just at the apex; the joint is longer and broader in the adult animals 

 than in the young; the front margin is convex, with three or four short spines and two 

 longer ones at the apex; the hind margin is convex, set with eight or nine equidistant 

 spines, the uppermost being slender and bristle-like, and the margin between them fringed 

 with soft hairs; the four undermost spines are very stout, and between them there is a 

 strong pectination, consisting of long, spine-like teeth. The metacarpus is a trifle shorter 

 than the carpus in the adult males, but fully as long in the younger animals; the hind 

 margin is pectinated; the front margin is convex. The dactylus is stout and curved; 

 it is not half as long as the metacarpus. 



The fifth pair (Pi. XIII, fig. 25 — 28) vary a little in length from one individual 

 to another, but are in the adult male usually fully as long as the head, peraeon, pleon, 

 and urus together. The femur is considerably broader than that in the sixth pair, and 

 a little broader than that in the seventh; the front margin is concave near the base, with 

 the lower half straight and armed with seven or nine spines; the hind portion of the 

 femur is dilated and laminar in order to protect a part of the leg when folded up, and 



