Potassium Hydroxide hy Dicramtra vinula. 409 
surface is clad with loDg hairs (Figs. 13 and 14), the 
latter with ordinary scales, while the sides offer a very- 
beautiful series, passing ventral-wards, showing the 
gradual modification of the ordinary scale into the long 
hairs (Figs. 15, i.-iv.). Situated just dorsal and slightly 
external to the insertion of the antliae, and beneath 
the lateral edges of the labrum, is a pair of small 
appendages, consisting of a single joint only, and clad 
at their free extremities with a dense tuft of hairs 
(Fig. 13, mn) ; three fine fibres (muscular or tendinous) 
pass to each of these, two are inserted near the outer 
margin of, and one near the inner margin of the 
junction with the head, I could not detect any movable 
articulation, though the presence of these fibres would 
lead one to expect it. These appendages appear to me 
to be, without doubt, the mandibles. If this prove 
correct, it may throw light upon the systematic position 
of B.. presinana. 
I am aware that, in many particulars, these notes 
lack completeness ; I thought it best, however, to bring 
them together without further delay, in the hope that, 
by drawing attention to the secretion of alkaline liquids, 
others with more leisure for investigation than falls to 
my lot may be induced to take up and further extend 
the inquiries thus begun. 
