MR. TUFFEN WEST 
411 
A few words will describe all that need be said, in the present place, respecting some 
modifications of tenent hairs for sexual purposes. 
An example is given from Arnara (fig. 22), to show that there is no essential dif- 
ference between these and the large tenent hairs which have just been described at 
length, other than as relates to their size ; in their number, 111 on each hand, the two 
entirely agree. They are arranged thus : on each side of the first tarsal joint, 2G ; of the 
second, 26 : of the third, 20. Greater diameter of the membranous expansion of a large 
one, -002 inch ; entire length of shaft, -008 inch. 
The next example, from the hand of the male Carabus granulatus (fig. 23), possesses 
an especial interest from the features which it presents, in relation both to the size and 
to the number of the tenent hairs*. In size they stand about midway between large 
and small; diameter of expanded part, which is orbicular in outline, '0007 inch; extreme 
length of a tenent hair from this beetle, -0055 inch. Speaking of their number, it may 
be said that they are very numerous ; I have not yet counted them. They arise from 
the first three joints only of the tarsus. Towards the free end, for half their extent, they 
are greatly corrugated, just like stiff leather, as a strap, when much bent about, becomes 
covered with transverse wrinkles. This corrugation is present on all tenent hairs desi ined 
for sexual purposes; observations on the habits of the beetles possessing them satisfac- 
torily account for the appearance, and prove that the mode of its formation is as above 
supposed. When in the live-box, beetles having such appendages to their hands press 
them firmly against the glass cover, and then, upon these as fixed points, the body is con- 
tinually swayed ahout in every direction. And whoever has observed the males of the 
large Carabl attached to their mates in copuld, by whom they are dragged about in stony 
or gravelly places, will see that the rude shocks to which these tenent hairs must be con- 
stantly exposed, under such circumstances, will readily account for the corrugations 
described, on parts having a leathery texture. 
Amongst the Staphylinidro, the " anterior tarsi » are « often dilated in the males 
tenent hairs for sexual purposes are often very well developed ; in some species they are 
very numerous, in others very few in number. Where present, they are of a softer 
texture than those last named, so that indications of corrugation are but very slight In 
Oeypus olens (fig. 24) and Creophilus maxillosus, the tenent hairs form a dense cushion 
on the under-surfaee of the four basal joints of the anterior tarsi. Their free ends are 
especially soft, so that it is difficult to say what should be considered their real shape. 
When viewed in action, from the closeness with which they are packed, they have a ten- 
dency to assume a form varying from orbicular, even to slightly hcxagona ; when dragged 
the glass they become lengthened into oval, elliptic, and fusiform shapes. R. Beck 
The 
has noticed that the expansions shrink and almost disappear when these insects are placed 
under the influence of chloroform : this I had not myself noticed ; but the almost complete 
disappearance of the expansions in dead specimens is satisfactorily accounted for by u. 
On the upper surface of the expansions, in the two examples above named, there are some 
% « 
Carabidje." €t Anterior tarsi grea 
•Wefctwood 
t Ibid. vol. i* p. 163. 
VOL. XXIII. 
3K 
