414 MR. TUFFEN WEST ON THE FOOT OF THE FLY. 



of tencnt liairs, it will be uunecessary to do more tliau state the size. Length -0056 inch, 

 of subtriangulav expansion -0006 inch, breadth of ditto -0004 inch. 



All the Longicorn beetles Avhich I have examined have the tenent hairs composing their 

 tarsal cushions formed like the above ; I figm-e additional examples from Aromia moschata 

 (fig. 42) and Tnonus coriariiis (fig. 43). 



On the tarsi of Cantliaris resicatoria (fig. 28, PL XLII.), and Ilylabris Ciclwrice 

 (fio-. 29, PL XLII.), a similar modification of hairs for tenent purposes is met with. 



I figure hairs of this kind from the tarsi of Fliosphuga (fig. 44, PL XLIIL), of Tlmarcha 

 (fig. 45), of Telephora (fig. 46), Coccinella (fig. 47), and Forficida (fig. 48). 



The Curculionidte, it has been already mentioned, have their tarsi well furnished with 

 tenent hairs (fig. 49)*. 



In the Chrysomelida?, these parts diflTer 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 

 downv.-ards, 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 haks, 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 Avould be the result. 



In a species of Ualtica (fig. 54) the expansion of the tenent hairs has generally, for the 

 purpose of obtaining additional hold, two (or sometimes three) minute 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 imder surface of its robust tibiie (the tarsi are in the 

 most rudimentary condition, as single, very indistinctly-defined joints), a moderate number 

 of large Avell-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 titiffuis ; those which are seated near the extremity of the joints have a very peculiar 

 abrupt ]3end, 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, in 

 which it is most clearly to be observed) bend towards the glass of the live-box, attach 

 themsch^es by pressing their expansions upon the glass, remove, and again fix themselves 

 in the same Avay. Por 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. B. Beck, 

 however, noticed similar facts, at a time Avhen I had no idea that he was worldng 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" the "cushioned tarsi" of the Curculionidee "indicate strong adhesive rather than cursorial 

 powers." — Westwood, Introd. vol. i. p. . 



