12 CAKI. noVALLILS, AMriIIl'()UA riyi'EKIII)KA. 



loiigcr {-^ : '2). 'Jliu tliird and tourtli sugiuciits are thc loiigcst, thc lirst and wcvcnth tlic 

 shortcst. 



'J'Ir! fiTst pair of 2>ereiopoda (Pl. I, fig. 12) are loiig and slender. The epiiaeral is 

 longer than deep, almost quadrangulai-, tlie lower corncrs rounded; thc epiinerals of thc 

 tollowing pairs have all the same form. The fem ur is four times longer than broad, 

 linear, tlie margins smooth. The genu and tibia ai-e short, the carpus elongated, almost 

 linear, fringcd >vith long slender hairs along thc posterior margin and at the lowcr 

 anterior corncr. The metacarpus is clongatc-ovate, eonsiderably shorter than the carpus 

 (4 : 3), beset with long slender hairs all aroiuid, thc lower anterior corner feebly produced 

 on both sides of the base of the dactylus; the posterior margin is sparingly serrated. 

 The dactylus (Pl. I, tig. 13) is very long, longer than half thc metacarpus (11:18), 

 straight, with a dccj) circular noteh at the base. At the bottom of this notch is a small 

 hole, probably the opening for a mctacarpal gland. Thc posterior margin of the dactylus is 

 bordered with very short fine hairs. Long string-formed glaiids are to be scen in all the joints. 



The second pair (Pl. I, fig. 14), are longer than tlie first. The fe mur, of the same 

 form as in the first pair, carries a few long hairs at the lower posterior corner; the genu 

 and tibia are short, provided with some hairs. The carpus is scarcely longer than thc 

 metacarpus, both less richly beset with hairs than in the tirst pair. The metacarpus without 

 projections. The dactylus feebly curved, as long as half the metacarpus, provided with 

 a small hole at the base. Glands as in the first pair. 



Thc third and fourth pairs (Pl. I, fig. 5, and Pl. II, fig. 6 and 7) are equal in length 

 and of the same form. The genu is uncommonly long, smooth; the three following joints 

 are longj microscopically serrated along the posterior margins, and provided with equidistant, 

 very minute spines. The dactylus is feebly curved, longer than half the metacarpus. 

 Glands as in the first pair. 



The fifth pair (Pl. II, fig. 8), as in all known species of the genus Tyro, are devc- 

 loped into a kind of jumping organ; at the same time they serve as a good Aveapon, the 

 femur being produced into a very strong spine. The femur is long, linear, slightly 

 serrated along thc anterior margin and coarsely along the posterior; it is shorter than the 

 three following joints together. The lower anterior corner projects into a very strong, 

 straight, sharp process, twice longer than the genu. The tibia is much shorter than 

 the carpus, both are smooth, almost linear. The metacarpus is very slender; it equals 

 scarcely a third of the length of the carpus. The dactylus is small, feebly curved. 



The sixth jmir are eonsiderably shorter than the fifth. The femur is a little more 

 dilated, broader below. The tibia is longer than the carpus, the metacarpus as long as 

 the carpus; these three joints are slightly serrated along the anterior margins. The 

 dactylus is curved, with a hole for the metacarpal gland at the base, (Pl. I, fig. 15). 



The seventh pair (Pl. I, fig. 16 and 17) are shorter than half the fifth pair, and about 

 as long as the femur af the same pair. The tibia is longer than the carpus, the meta- 

 carpus is elongate-ovate, finely serrated along the antei-ior margin; it is longer than the 

 carpus. The dactylus is long, feebly curved. 



Branchial säcks are attached to the epimerals of the second to sixth pairs, those of 

 the fifth jjair are the largest. 



