248 Dr. Arzettus’s Odfervations on the Genus Paufus. 
The Antenne are very remarkable, and different from thofe of all 
other infeéts, not only by their confifting of no more than two 
joints, but alfo by their fingular mechanifm. The under-joint is 
thick and almoft round knob, truncated at both ends, and below on 
the outfide furnithed with a little bight ball, moving in a cavity 
on the head, juft before the eye, between the clypeus and the an- 
terior angle of the eye-focket. This ball is the pivot on which the 
whole antenna rolls or performs its rotatory motion. It is very 
vifible at its root, and eafily miftaken for an eye, being quite globu- 
lar, and, by continual rubbing, highly polifhed. The upper joint is 
alfo a kind of knob, but of a very different nature, and curioufly 
conftructed. In the front it is outwardly marked with a raifed 
line, or an edge, running from the bafe to the vertex, and behind 
elongated into a tube or a hook pointing inwards. Beneath it is 
furnifhed with a pedicle, which having a ball at the end, and being 
inferted in the under-joint, towards the. outfide of its top, as into a 
focket, makes the upper-joint qualified for a feparate motion, in- 
dependent of that of the whole antenna. And as a proof that this 
is really the cafe, it is to be obferved that there are fcarcely two 
antennz to be met with having the elongated hind part of the 
upper-joint pointing exaétly the fame way, though the under-joint 
remains in its ufual pofition; which makes it very difficult to de- 
termine the true and moft natural direétion of this hind part, which 
however, I fhould think, mutt be either juft above the under-joint, 
or a little on the outfide of it. Linné gives to this part the name 
of hook; and fo it is in my fpecies, but in his own it refembles more | 
a tube or a blunt fpur, or rather it is nothing elfe than a fhort 
contracted elongation of the upper-joint. But, having made this 
remark by way of explanation, I fhall not fcruple to retain the 
original term uncinafa, as applied to the upper-joint, called by 
Linné 
