EXTERNAL ANATOMY OF INSECTS. 691 
crooked like the claws of the eagle *, and the posterior 
one of the Hopliz is bent like a hook”; they most com- 
monly diverge from each other; butin the Rutelide, 
Anoplognathide, &c., they are perfectly parallel, and in 
the former often inflexed*. With regard to other append- 
ages of the part we are treating of, if you examine the 
stag-beetle and many other Lamellicorns, you will find 
between the claws a minute but conspicuous joint ter- 
minated by two bristles which seem to mimic the ungula 
and its claws; these parts are what are denominated in 
the table the palmula, plantula, and pseudonychia : in the 
stag-beetle these are long4; in the Melolonthide short ° ; 
and in many Cetoniade they resemble an intermediate 
claw. 
The most remarkable of the appendages of the tars? are 
to be looked for on their under side or sole (solea), and 
are the means by which numbers of insects can overcome 
atmospheric pressure and walk against gravity. Many 
of these have been fully described in a former letter ‘ ; 
but much that relates to them was there omitted, which 
I shall now detail to you. Four kinds of pulvilli, as I 
would call these appendages, are found on the sole of in- 
sects, upon each of which I shall make a few remarks. 
The first is a cushion or brush composed of very thickly 
set hairs or short bristles : examples of this you will find 
in the majority of Tetramerous and Trimerous beetles. In 
Chrysomela, Timarcha, &c., there is one of these cushions 
on each of the ¢hree first joints; in Prionus, Liparus, 
&c., there is a pair; and in Coccinella on the two first ; 
* Pirate XXVIII. Fic. 53. b Ibid. Fic. 51. 
© Tbid. Fie. 47. ¢ Tbid. Fic. 56. aw, f*. 
* Ibid. Fic. 49. ay, f*. f Von, LL. p. 322—. 
DNase 
