254 SENSES OF INSECTS. 
not discoverable upon dissection, in the interior of the 
head of any insects, some organ that may be deemed, 
from its situation, under what we have called the nose 
and nostrils, the seat of the sense we are treating of. 
The common burying-beetle (Necrophorus Vespillo) is 
an insect remarkable for its acuteness of smell, which 
enables it to scent out and bury, as was formerly related 
to you, the carcases of small animals. ‘Take one of 
these insects, and kill it as formerly directed,—examine 
first its nose: in the middle of the anterior part you will 
see a subtrapezoidal space, as it were cut out and filled 
with a paler piece of a softer and more membranous tex- 
ture. Next divide the head horizontally ; and under the 
nose, and partly under this space, which I call the rz- 
narium or nostril-piece>, you will find a pair of circular 
pulpy cushions, covered by a membrane transversely 
striaied with beautifully fine stria. These are what I 
take to be the organs of smell, and they still remain dis- 
tinctly visible in a specimen I have had by me more 
than fifteen years. A similar organ may be discovered 
in the common water-beetle (Dytiscus marginalis), but 
with this peculiarity,-that it is furnished with a pair of 
nipples. I have before described an analogous part co- 
vered with papillee, in shna viatica, and you will find 
it in other insects‘. Perhaps at first this part may seem 
merely a continuation of the palate; but if you consider 
the peculiarities in its structure just noticed, it is evi- 
dently a sensiferous organ; and as the sense of smell ap- 
pears to reside in the head, this is its most probable seat. 
But by what channel scents act upon it,—whether they 
* Vou. I. p. 350—. » Vor. III. p. 481—. 
* Ibid. p. 455—. 
