364 Anatomy and Physiology of the Family Nepide, (Apt 
Taste and Smell—The work on these insects as far as carried — 
out, furnishes no suggestion as to the location of the sensesol 
taste and smell, and, as far as my knowledge goes, their existence 
rests wholly on analogy. In some insects, as the Silphida,smel — 
is obviously present and directs them to their food; and tastes 
probable in insects possessing soft tongues. 
Hearing —Hearing i in the Insecta is usually located wak: 
mists in the antennæ. This is made very probable by investige | 
tions similar to those of Mayer, the physicist, on the mosquito. l 
This observer, by watching through the microscope the hairs oo 
a mosquito’s antenna, found that they responded by vibrations to a 
certain sounds that he produced; the hairs, being of different 
lengths, responded to several sets of vibrations, but pe | 
strongest to the note emitted by the female mosquito. 
Other experiments of a similar nature, and the fact skp iene , 
insects appear deaf when the antennæ are removed, add force t f 
the conclusion that they serve as organs of hearing. per 
sects, the Orthoptera, for instance, have special organs for i z 
reception of sound, either on the thorax or at the base of o l l 
terior legs. d t 
In the Nepidz, there are certain conditions in the i sei l 
the antennæ that seem to me favorable for the increase 
vibrations. The Belostoma and Perthostoma have each of 
antennæ enclosed in a vaulted cavity, which is suggestive 
resonance chamber. Each chamber extends into the eye 
it, and separates the fibers of the optic nerve into two 
and its opening below the eye is partly closed, so i 
_ toward the median line of the head, through which 
may be protruded or withdrawn. The antenne are 
with sensitive hairs (Fig. 18), which doubtless 
roughened surfaces come together. 
Sight—The Nepide have two prominent cont” 
on each side of the head, but no ocelli. They are 
nally by a modification of the integument, which ans! 
nea of the vertebrate eye. This is divided i 
hexagonal facets, underneath each of whi 
