382 Transactions of the Society. 



runs a strong chitinous blade, which is widest at the proximal end. 

 On the tibia this blade is replaced above by a great chitinized 

 papilla which bears the very large tactile hair ; below, however, 

 the blade is present along the anterior part of the leg, but is cut at 

 its edge into about seven great comb-like teeth radiating like a 

 fan, but directed downward. 



It will be seen that the difference from Kramer's species here 

 is that this comb-like arrangement is in single row directed down- 

 ward along a median blade on the joint itself, instead of being on 

 each side of a hair springing from the distal edge, and this differ- 

 ence is kept up in the still more curious second leg, in which case 

 the blade is present on the upper and under sides of the tarsus and 

 on the upper side of the tibia, but on the under side of the latter 

 joint is a fan-shaped comb-like blade, similar to that on the first 

 leg, but more projecting, and on the under side of this leg the 

 comb-like blade is carried all along the great second joint of the 

 leg, and is there cut into two divisions, the proximal having the 

 teeth (about eight) radiating from an almost semicircular blade, 

 and the distal being long, with the teeth (about twelve) directed 

 more forward. The whole forms a very singular leg. That these 

 blades and comb-hke processes may in their origin be modified 

 hairs seems probable, both from Kramer's species and from the 

 position of some curious serrated hairs in the present species 

 (fig. 13, second joint above ; fig. 15, third and fourth joints below). 



The curious apparatus at the posterior end of the hypopial 

 nymph, apparently for holding the hairs of the mole, seems to 

 differ somewhat from the corresponding part in Haller's species. 

 It consists of a median concave channel in which the hair lies 

 longitudinally ; this is overlapped by a flexible, lip-like organ on 

 each side, the two lips slightly crossing when there is not any hair 

 beneath them. They are provided with powerful retractor muscles, 

 which draw them closer to the body. Each lip bears a large 

 chitinous plate on its inner surface, and on the inner side of this 

 plate is a strong chitinous band with transverse ridges; on the 

 abdomen, immediately below each band, is a circular chitinous 

 plate with radiating ridges, and the hairs are firmly held between 

 the bands and the circular plates. 



I have utilized the present paper to illustrate and describe 

 another unrecorded species, the life-history of which I worked out 

 some time since, and which is so far connected with that hitherto 

 referred to that it forms a good example of a species which in the 

 adult form assumes the hypopial appearance, as contrasted with 

 the foregoing species, which has a true nymphal hypopial stage. 

 In the paper before referred to, I gave the life-history of an Acarus 

 which I called Disparipes homhi, the adult female being found on 

 humble-bees, and having an extremely hypopial appearance. It is, 



