PROTECTIVE RESEMBLANCE. 607 
back. The caterpillars of the geometrid moths often won- 
derfully mimic the stems of the plants they feed upon, in 
color and markings, even to the 
warts and tubercles on their skin. 
As an example of possibly con- 
scious mimicry or effort at conceal- 
ing their nest from the search of 
their enemies, may be cited the trap- 
door spider observed by Moggridge 
in Southern Europe. This spider 
digs its hole among moss and small 
ferns, and after the trap-door is 
made the top is covered with growing 
neng Bepicat insect (Phy ferns, etc., transplanted by the spider, 
and the deception is so perfect that 
Mr. Moggridge found it difficult to detect the position of 
the closed trap, even when holding it in his hand. 
Mimicry of other insects is of 
very frequent occurrence, certain 
flies resembling bees in appearance 
and the sounds or buzzing they 
make; the Syrphus flies closely 
imitate wasps. Fig. 545 illustrates 
a case observed by Belt in Nicara- 
gua, where a wasp (Priocnemis) is 
mimicked by a hemipterous insect 
(Spiniger luteocornis Walker, the 
left-hand figure) in every part, 
even to its vibrating, brown, semi- 
transparent wings and its wasp-like 
motions. Here the bug is evidently 
protected by its resemblance to the 
wasp, for whose ferocity and sharp 
sting all unarmed insects have 
great respect. 
Some butterflies are distasteful Fig. 544,—Stick insect, 
to birds, and there are other but- 
terflies which have no bad taste, but closely resemble in 
color such species as are passed over by birds. Thus, 
