28 ON APPENDAGES TO THE FEET OF INSECTS. 
the hind legs of some aquatic insects, when they are not used 
either as aids to progression or for the capture of prey, the claw- 
hairs are scarcely distinguishable from other hairs by which they 
are surrounded. The five “supplementary claws”’ (slightly modi- 
fied hairs) of Hpeira, and still more noticeably the claws found by 
the author along the entire under surface of the tarsi of Pholeus 
phalangioides, were mentioned as supporting this view. 
This, the first portion of the paper, after recalling the brilliant 
researches of Professor Huxley on various dissimilar tegumentary 
structures formed from hairs in the higher animals, concluded 
with a few reflections on the equally remarkable series of modifica- 
tions of the same essential part in the Articulata. 
In the second portion of the paper the structure of sucking-disks 
of a more eomplicated nature was somewhat minutely treated. 
The most complex in structure was stated to occur in the feet 
of the Wasp, Hornet, and some of the Bees, in which it is a single 
central organ, situated beneath the ungues. Its various parts were 
described, with their appearance whilst in action. It was stated 
that in-some, as the Hymenoptera, the whole organ was soft and 
contractile, to enable it to be readily put away out of danger, as 
well as preserved in efficient condition for action when required. 
It was believed that the whole of the Lepidoptera were also fur- 
nished with a similar organ, but that, being of firmer consistency 
in them, it was less liable to injury ; and the author had been unable 
to satisfy himself that, in any of this tribe, it possessed such an 
amount of contractility. . 
The bifid sucker of MJalachius eneus in the Coleoptera, and 
of several of the Pentatomide amongst the Hemiptera, was then 
described, together with the hood-like sucker (“‘vesicle”’ of authors) 
terminating the tarsi in Thrips, in various species amongst the Ce- 
cropide, and in many of the Acarida. Several Tipulide were men- 
tioned as presenting the only instances of a sucker beneath the 
claws amongst the Diptera. 
The idea was broached thatthe terminal sucking-disk was perhaps 
an additional tarsal joint modified to serve a special purpose. 
The paper was illustrated by numerous drawings and specimens ; 
one of the latter, a beetle, possessed of as perfect powers of 
walking on glass as a fly, was shown living. 
