STATES OF INSECTS. (Jmago.) 335 
of stiffish hair; in the female all are equally slender, 
and not so hairy. In Carabus, &c. the four first 
joints of these tarsi in the males are dilated, and furnished 
with a brush or cushion: in the Silphida, also, the same 
circumstance takes place. In Harpalus, and Silpha 
americana, the four anterior ones are similarly formed 
in this respect. But one of the most remarkable sexual 
characters, in this tribe of insects, that distinguish the 
males, are those orbicular patelle, furnished below with 
suckers of various sizes, and formed by the three first 
joints of the tarsus, which are to be met with in the Dy- 
tiscide, &c.; but as I shall have occasion to treat of these 
more fully in another Letter, I shall only allude to them 
now. ‘The second pair of tarsi have in these also the 
three first joints dilated and cushioned*. In Hydro- 
philus piceus, another water-beetle, the fifth joint of the 
tarsus is dilated externally, so as to form nearly an equi- 
lateral triangle’. Christian, a German writer on the Hy- 
menoptera, has described some very singular appendages 
which he observed on the first joint of the four posterior 
tarsi of Xylocopa latipes. These were battledore-shaped 
membranaceous lamine, with a reticulated surface, of a 
pale colour; which were fixed in pairs by the interven- 
tion of a footstalk to the above joint, on which they 
sometimes amounted to more than a hundred: the use 
of which, he conjectures, is the collection of pollen®: 
I possess two specimens of this bee; one has none of 
_ these appendages, and on the other I can discover them 
only in one of the tarsi—from which circumstance I am 
* Prate XV. Fie. 9. b Ibid. Fic. 8. 
© Christ. Hymenopt. 118. t. iv. f. 3. 
