INTRODUCTION. 
59 
some authors as absorbents. From having observed 
them chiefly in long and slender trunks, Reaumur 
was led to conceive, that their only use is to render 
that organ more steady, by affording numerous points 
of support, and adhering in some degree to the sub- 
stances into which it is inserted; — an explanation 
rendered highly probable by the fact, that the long 
and slender ovipositors of Ichneumons, and many 
other insectB, are generally provided with some point- 
ed projections near the tip, evidently intended for 
this purpose. — Several of the figures on Plate I. are 
designed to illustrate the structure of the organ just 
described. Fig. 9, is a magnified view of the trunk, 
showing its general form, and the projecting points 
near the tip (a). Fig. 10, is a highly magnified sec- 
tion, exhibiting the two portions (a, b) of which it is 
composed, each of them tubular (d, d), and forming 
by their junction a central canal (e). Fig. 11, is 
another section, representing the under sidp. 
The two portions of which the proboscis is com- 
posed, seem to be analogous to the maxilla; or un- 
der jaws of the mandibulated tribes, and to receive 
their great development at the expense of the other 
oral appendages, most of which are small and incon- 
spicuous. This is not the case, how’ever, with the 
labial palpi, which are generally of considerable size, 
and curved upwards in such a manner as to form turn 
projecting points in front of the head. These or- 
gans are covered with hair-like scales, are usually of 
a somewhat conical shape, and consist, for the most 
part, of three articulations. (See PI. I. fig. 12 a 
