414 MR. TUFFEN WEST ON THE FOOT OF THE FLY. 
of tenent hairs, it will be unnecessary to do more than state the size. Length -0056 inch, 
of subtriangular expansion -0006 inch, breadth of ditto -0004 inch. 
All the Longicorn beetles which I have examined have the tenent hairs composing their 
tarsal cushions formed like the above ; I figure additional examples from Aromia rnoschata 
(fig. 42) and Prionus coriarkts (fig. 43). 
On the tarsi of Cantharis vesicatoria (fig. 28, PI. XIII.), and Mylahris Cichoria 
(fig. 29, PI. XLIL), a similar modification of hairs for tenent purposes is met with. 
I figure hairs of this kind from the tarsi of JPhosphuga (fig. 44, PI. XLIIL), of Thnarcha 
(fig. 45), of Telephora (fig. 46), Coccinella (fig. 47), and Forficula (fig. 48). 
The Curculionidae, it has been already mentioned, have their tarsi well furnished with 
tenent hairs (fig. 49)*. 
In the Chrysomelida?, these parts differ from the above in no respect but size (fig. 50). 
An elegant form is presented by the tenent hairs of some beetles, which have them bent 
downwards, almost in a vertical direction, towards their bifurcate tips (figs. 51, 52). The 
hairs on the hinder part of these tarsi are simply bifurcate and terete ; and the various 
stages of specialization, from this to the perfectly developed tenent hairs, may all be 
traced on these appendages to a single tarsal joint. 
Niptus hololeucus has a small brush of tenent hairs in the neighbourhood of the claws, 
mostly underneath (fig. 53). If we imagine them to be cemented together, a rude idea of 
the Ply's foot would be the result. 
In a species of Haltica (fig. 54) the expansion of the tenent hairs has generally, for the 
purpose of obtaining additional hold, two (or sometimes three) minnte claws. I think 
this may explain Leeuwenhoek's description of the parts in the Weevil from apple-blos- 
soms, to which allusion was made in p. 395. 
The larva of Coccinella presents, on the under surface of its robust tibiae (the tarsi are in the 
most rudimentary condition, as single, very indistinctly- defined joints), a moderate number 
of large well-marked, trumpet-shaped tenent hairs (fig. 56). They are most numerous on 
the hind pair of legs, fewest on the anterior pair. The length of the largest is '005 inch ; of 
the expansion -0006 inch ; width of the latter, -0004 inch. About four or five, and these 
the largest, arise from the rudimentary tarsus, on its upper surface, and arch gently over 
the unguis ; those which are seated near the extremity of the joints have a very peculiar 
abrupt bend, at about one-third from their extremities. These tenent hairs are distinctly 
moveable ; I have repeatedly watched them (especially the long ones over the claw, m 
which it is most clearly to be observed) bend towards the glass of the live-box, attach 
themselves by pressing their expansions upon the glass, remove, and again fix themselves 
in the same way. For a long time I thought I must have been deceiving myself, though 
it is not easy to see how those which are seated on the upper surface of the limb can be 
made use of unless such a power of moving them be possessed by the insect. R. Beck, 
however, noticed similar facts, at a time when I had no idea that he was working in the 
same direction. I am compelled to the belief that a minute muscle is attached to the 
root of every well-developed tenent hair, as well as of every ordinary true insect-hair, and 
* « 
The structure of 
powers."— Westwood, ] 
than 
rial 
