40 
requested that I complete the work already begun. At the 
same time, he offered to have all of the specimens in Hawaiian 
collections shipped to me and generously placed all of his notes, 
dissections, and drawings at my disposal. All of this material 
is now before me as a result of this kind offer and of the 
assistance of Mr. Swezey, who shipped much of it. 
The genus Apterocvclus is peculiar in that it is wingless and 
without a labrum. It was stated by Waterhouse to be some- 
what related to the Chilian genus Sclerostomus, but by Sharp 
supposed to be closer to the genus Dorcus, and to this latter 
view I agree. In fact, all specimens seen appear superficially 
like very degenerate and chubby species of Dorcus. Among 
the individuals of the genus there is also a very great amount 
of variation. I have had the opportunity to study one hundred 
and thirty-six specimens and as a result of this, supplemented 
by a careful examination of the dissections and drawings of 
the genitalia of numerous divergent forms, made by Mr. Gif- 
fard, have come to the conclusion that there is but one species, 
honoluluensis, and that all other so-called species are but vari- 
ants of this. It seems to me that we have here a case of a 
species of Dorcus or of a closely related genus having become 
established at a very ancient time on what is now the island 
of Kauai, and of having undergone subsequent to that time a 
great degree of modification, chiefly along lines of degenera- 
tion. The species having once lost its stable status, soon 
acquired a great deal of plasticity which has been retained to 
the present date. The degeneration is shown in such ways as 
the absolute loss of wings and the resulting reduction of the 
entire afterbody, particularly evident in the shortening of the 
metathorax, as is clearly to be seen beneath in the very short 
metasternum, and the shortening and rounding of the elytra, 
a character that is always to be noted in species which have 
been long without wings; the loss of the labrum; and the 
shrinking of the integument, particularly noticeable in the 
elytra of the males. The species has undoubtedly developed its 
subterranean habits* with the resulting enlargement of legs, 
3 Mr. Kusche told me that he found practically all of his specimens 
in old rotting stumps or at the base of the same, and that sometimes 
they were some distance below the surface. 
