164 Rey. H. Clark’s Catalogue of Halticide. 
therefore, to its subscribers that the following Catalogue was printed 
for me by Messrs. Taylor and Francis for private distribution among 
my correspondents, who had liberally entrusted to me their collec- 
tions of the group for examination: the present Number of the 
Journal was at that time going to press, and so it was suggested 
that, inasmuch as the type was already set up, no expense would 
be incurred, and perchance benefit might accrue, if the list were to 
appear as one of the contributions. Certainly, for my part, if by 
means of greater publicity further aid should be rendered in the com- 
pletion of the work, I shall be very grateful. 
The subject of the list is a continuation of those sections of Halti- 
cide formed by Iliger (Mag. fiir Insekt. 1807, p. 82) which have the 
posterior claw globularly inflated, and for which he proposed the 
names of Physapodes and Gidipodes. It was at first my intention 
to have terminated my Catalogue for the British Museum with the 
genus Cdionychis, this group being separated from others which 
follow by its generally more rounded and less parallel form and its 
more completely globular inflation of the posterior claw. I find, 
however, that though this obtains for the most part, there are some 
species (a few), in my own collection and in that of Mr. Baly, which, 
in both these respects, are connecting links between the two genera 
CGdionychis and Omophoita, De}. Cat. (this latter being, so far as I 
can discern, identical with Ptena, De}. Cat.). The genus Omophoita 
is, therefore, included in the proposed continuation of the monograph, 
which will thus include all species, not only with a globular, but with 
a more than usually dilated apical claw. 
The peculiar difficulty of the group (which has occupied me for 
nearly two years) consists in the marvellous tendency to variation 
which so many of the species exhibit ; and this difficulty, instead of 
being diminished, has been enormously increased by the liberality of 
my friends, from whose cabinets I have received several thousand 
specimens for comparison. If the material had consisted only of 100 
specimens, these 100 might readily have been resolved into apparently 
good and well-separated species; but inasmuch as an abundance of 
materials has supplied many examples which must be dealt with as 
connecting links between insects differing evidently one from the 
other, not only has the difficulty of the subject been increased, but 
it has become probable that other individuals, yet to be examined, 
may bring together as one species examples which at present ought 
to be considered distinct: however, be this as it may, I shall be 
very glad to examine and name any representatives of the group 
that may be entrusted to me; especially shall I be thankful for the 
