268 BRITISH TYROGLYPHID.E. 



downward and inward, and slightly serrated. A very 

 strong, somewhat similar, curved spine springs from 

 the under-side of each tibia near its distal end. There 

 are two or three short spines on the under- side of each 

 tarsus ; and one, rather larger, on the upper side of 

 that of the second pair. Ventral surface much arched, 

 projecting in the centre ; edges thinner and flatter. 

 Sternum short, joined to the epimera of the first pair 

 of legs. Epimera of the second pair free. Epimera 

 of the two hind pairs joined together at their inner 

 ends by a cross-piece. None of the epimera quite 

 reach the vulval sclerites. Vulva (PI. B, figs. 8, 10) 

 large and placed far forward, its anterior end being 

 between the coxae of the second pair of legs. It is 

 protected anteriorly by a thick, pointed, chitinous 

 band of a Gothic-arch shape, the point forward, and 

 posteriorly by a more rounded and thinner piece 

 fitting within the arch; these form an enclosure; 

 the labia of the vulva extend its whole length ; they 

 bear two pairs of very minute hairs. Anal opening 

 long, almost touching the hind margin; it has pro- 

 jecting labia lying together like knife-edges; and is 

 bordered by five pairs of spines of various sizes, of 

 which three form a triangle on each side. 



The Male (PI. XIV, fig. 1), as will be seen by the 

 measurements, is much smaller than the female ; the 

 difference is almost wholly in the size of the abdomen. 

 Cephalothorax similar to that of the female ; but the 

 papillae from which the two spines on the dorso-vertex 

 spring are not so large or projecting as those of the 

 female. The sternum is longer than that of the female, 

 but otherwise similar. A chitinous cross-piece joins 

 the ends of the epimera of the second, third, and fourth 

 pairs of legs instead of only the last two. There is a 

 singular branched hair (PL XVII, fig. 4) on each side 

 of the body between the coxae of the first and second 

 pairs of legs. It is very minute, not above 25 ju long. 

 I could not see it on the whole creature, and only dis- 

 covered it by dissections of the exo-skeleton. Abdo- 



