DESCRIPTIONS OF GENERA AND SPECIES. 263 



only portions which show from the dorsal aspect are 

 the mandibles (PL XIII, fig. 2) and palpi ; the former 

 are usually more or less extruded, and are stout and 

 bulbous at their proximal ends. 



Body. Abdomen raised in the centre, particularly 

 toward the posterior end, and with a somewhat thin 

 and depressed lateral margin ; the actual edge is 

 usually cut into a series of more or less trifid pro- 

 jections, the outer lobes of each projection being the 

 larger and rounder, and the central lobe being a small 

 papilla bearing the palmate hair. This trifid shape is 

 not so well marked on the hind margin. The epimera 

 of the first pair of legs are joined to a short sternum, 

 those of the other pairs are free. The vulva is large, 

 extending from a little in front of the third to consider- 

 ably behind the fourth epimera ; it has wide open lips, 

 and is protected by a short, strong, transverse, chitinous 

 piece anteriorly ; and by a long, fine, chitinous band of 

 a reversed horseshoe shape, with prolonged curved 

 ends posteriorly. The so-called anal projection (bursa 

 copulatrix) is long and somewhat conical. 



Legs short, almost entirely hidden from the dorsal 

 aspect ; tactile hairs on first pair more than twice the 

 length of the tarsus ; on second pair about as long as 

 the tarsus ; on the other pairs small and without the 

 tactile character. Caroncles large and trifid ; there is 

 a fine short hair on each tarsus just above them, two 

 farther back, and one or two other small fine hairs on 

 most of the other joints except the coxse. 



MALE (PL XII, fig. 1). 



The male is much smaller and more active than the 

 female; the body is rounder, and the vermiform 

 wrinkles much less pronounced; it is more granular. 

 The trifid projections are absent from the periphery, 

 the cephalothorax is longer in shape, the rostrum 



