the Larva of Collyris emarginatus, 89 
natus; the eighth tergite pears on each side three small 
forwardly-directed hooks and its posterior margin is 
fringed with sete; the terminal segment is armed on its 
posterior margin above with eight short spines arranged 
in two groups of four on either side of the middle line. 
In fact, such ditferences as exist between the two larve 
may be regarded as specific rather than generic. In one 
feature the Hongkong larva differs markedly from C. 
emarginatus; the metathorax is bent down almost at a 
right angle to the mesothorax and the first abdominal and 
succeeding segments are again bent up at an acute angle 
to the metathorax, thus producing a very sharp flexure of 
the body in this region. I cannot be sure, however, that 
this is not due to the undue contraction of the specimen 
after being placed in alcohol. The burrow is 24 mm. 
long and about 3°5 mm. in diameter, it has been formed 
by the excavation of the central medulla of pith; the 
affected part of the stem is dilated, being 7 mm. in 
diameter, whereas above and below the burrow it is only 
4 mm. in diameter. This, I expect, is a pathological 
result of the injury caused by the larva. I have observed 
something very similar in the stems of a herbaceous plant 
tenanted by ants, that I found at the foot of Mt. Penrisen in 
Sarawak.* The consequence of this dilation of the stem 
is, that the burrow itself is relatively of much greater 
diameter than that made by the emarginatus larva; the 
dilation appears to be caused, not by a thickening of the 
wood, but by the expansion outwards with concomitant 
thinning of the walls, just as a bulb may be blown in the 
middle of a glass tube. It would be interesting to learn 
if this dilation of the stem and expansion of the burrow 
occurs synchronously with the growth in size of the larva. 
Mr. Muir’s observation that the larva, when seizing its prey, 
rushes a short distance out of its burrow, is of considerable 
interest in connection with the fact that the entrance to 
the burrow cannot be enlarged by the larva as it increases 
in size. The entrance to the burrow of a Cicindela larva 
is a miniature pitfall, the head of the larva being the 
bottom of the trap; when an insect stumbles into the 
pitfall it is seized and the captor falls down to the bottom 
* If this interpretation is correct it lends considerable support 
to the view that the enormous swellings on the stems of myrme- 
cophilous plants of the genera Myrmecodia and Hydnophytwm 
originated as pathological responses to irritant stimuli. 
