DESCRIPTIONS OF GENEKA AND SPECIES. 277 



the lobe. Exterior to tlie lobes and trench there is a 

 broad raised belt, sloping upward toward its outer 

 edge ; it extends all round the abdomen except the 

 posterior margin ; there is a small raised lobe in the 

 centre of its anterior part. There are four minute 

 chitinous spines, or points, round the posterior margin, 

 and a pair near the anterior margin. Legs of moderate 

 length ; the fourth pair about reach the posterior 

 margin of the abdomen. The two front pairs are the 

 thicker. The coxa is rounded, the proximal ends of 

 the femur small ; thence the leg gradually increases in 

 thickness until the distal end of the bell-shaped genual, 

 whence it gradually diminishes. The tarsus is nearly as 

 long as the three previous joints, but this varies a little 

 in the respective legs. There is the usual tactile hair 

 on each tibia, those on the two anterior pairs are the 

 longest. There are two strongly serrated hairs on the 

 femur and one on the genual of the first leg, and one 

 on the genual of the second leg ; the serration of these 

 hairs is usually coarser at the distal than at the proximal 

 ends (PI. XVI, fig. 12). There are a few fine hairs on 

 the tarsi, and one or two on some of the other joints. 

 The tarsi are terminated by a long- shaped caroncle and 

 fine claw. The chitinous skeletal pieces of the under 

 surface of the cephalo thorax are as follows : some 

 short distance behind the maxillary lip is a curved 

 transverse band, concave anteriorly ; from the centre 

 of this band the sternum runs straight backward in the 

 median line, just passing the posterior edges of the 

 second coxae; then the sternum bifurcates; the branches 

 are much thinner than the true sternum, and join the 

 antero-lateral part of the undermentioned vulval ring. 

 The epimera of the first pair of legs join the branches 

 of the sternum rather anterior to their centres ; those 

 of the second pair of legs join the vulval ring almost 

 at the same point as the branches of the sternum. The 

 short epimera of the third leg do not join the vulval 

 ring ; there are not any epimera to the fourth leg 

 which show externally. The vulva is very large, 



