278 MB. A. D. MICHAEL ON SOME TJITDE SCRIBED 



Male. 



The smaller size is what strikes the observer first. It will be 

 seen by the measurements that the male is three quarters or 

 two thirds of the length, and is about two thirds of the breadth 

 of the female ; the difference in size being almost entirely in 

 the abdomen. With the exception of the size, there is a great 

 resemblance between the sexes ; and although there are numerous 

 and considerable differences in detail, they are not greater than 

 those usually found between the male and female in this genus ; 

 no one would doubt their belonging to the same species. 



Cephalothorax similar to that of the female ; but the papillge, 

 from which the two spines of 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 inner ends of the epimera of the second, 

 third, and fourth pairs of legs, instead of only the last two. 

 '^here is a singular branched hair (fi.g. 12) on each side of the 

 body, between the coxse of the first and second pairs of legs ; 

 it is very minute, not above "025 millim. long; I could not see it 

 on the creature itself, and only discovered it from dissections of 

 the exoskeleton. 



Legs. — These are stouter and are longer, in proportion to the 

 abdomen, than those of the female ; the tarsal joints, however, 

 are considerably shorter and more conical than those of the 

 opposite sex ; and the tibiae, particularly in the two hind pairs of 

 legs, and also the third joints of the fourth pair of legs, are very 

 much longer in proportion. There is another singular arrange- 

 ment in the two hind pairs of legs which is entirely absent in the 

 female. These legs have a decided curve inward, and the third 

 and fourth joints, particularly the fourth joint of the fourth leg, 

 increase rapidly in thickness at their distal ends, the whole in- 

 crease being on the inner side, so that this, at the distal end, 

 projects, forming a large curved point, from which the tarsus 

 curves away, forming the lower side of the point. To enable this 

 construction to work, the articulation, although close on the outer 

 side, is exceedingly loose on the inner side, the two joints being 

 there attached by a flexible membrane of considerable width, 

 generally bowed outwards, giving great play to the tarsus, pro- 

 bably for clasping purposes. The hairs on the legs differ very little 

 from those of the female, but the third and fourth tarsi of the 



