ON THE LARVA OF LIPHYRA BRASSOLIS. 263 



prolegs. Within this circle is a white projecting mass of tissue, 

 with a ridge along its summit from front to back, with parallel 

 striae running down to the margin. The crotchets are hooked 

 outwards, have a short flat base applied to the surface of attach- 

 ment, and, without forming two or three regular rows, are in 

 more than one row. The little smooth space outside them gives 

 them room for movement without being interfered with by the 

 hairs that clothe the rest of this under surface. 



These circles of crotchets, which are to all appearance identical 

 with the complete circles found on the prolegs of " Micro " larvae, 

 are not the ordinary crotchets at all, but an entirely new struc- 

 ture. The true crotchets exist in the young larva, but in this 

 full-grown one are merely represented by the strife on the central 

 fleshy mass noticed, which is really the true proleg; the crotchets 

 here existing are round the summit of the pillar, at the centre of 

 which the true proleg is here, as often, placed. Its method 

 of working must be very similar to that of the "Micro " full 

 circle, but, instead of having a central tendon as they have, it 

 has the whole proleg structure, by the movement of which it 

 must be expanded and contracted so as to take and relax 

 its hold. 



The true legs are rather small and rather thick, and densely 

 or at least very closely and regularly clothed with fine white 

 hairs, and terminate in a claw ; slightly hooked, slender as com- 

 pared with the last joint of the leg, dark in colour, making it 

 look very strong and sharp, and capable of being flexed, so as to 

 fold up on to the last (tarsal) joint of the proleg, reminding one 

 of the tibiae of Nepa or Mantis. 



The head is nearly colourless, about 1'7 mm. wide; centrally 

 below the mouth, and pointing backwards, is the labium or part 

 of it, a pale conical rather than cylindrical process ending in a 

 short chitinous tube (spinneret ?). On each side is a long palpus 

 (maxillary?) of three joints, the last very small, projecting ven- 

 trally, and apparently with a fleshy process (maxilla ?) towards 

 the middle line ; in front is a tolerably normal labrum, square 

 and notched below, with a good many short hairs on its anterior 

 surface. The antennae are very long, about I'l mm., and regularly 

 clothed with fine hairs ; I cannot recognize a basal joint, if there 

 is one; the next, therefore however, first, is very long, 1 mm., 

 and also thick about -22 mm. ; the last joint is a small square 

 piece about '1 mm. 



The labrum is very fixed in its position and moves little ; 

 even if I am deceived in this matter by having only stiff pre- 

 served specimens to deal with, it is certain that it fits down very 

 closely and tightly laterally in the maxillary bases, leaving in 

 front an oval opening between it and the labium, within which 

 the jaws are visible, with apparently some room for movement 

 in the cavity thus formed. 



