43 
pinging upon the eye, fig. 5. The anterior tibia may have the 
cuter margin multidentate, fig. 8; may be somewhat simple in 
outline, fig. 10; or have the apex decidedly tripalmate, fig. 11. 
Composite types may also be found as in fig. 9. The scutel- 
lum is normally moderately prolonged and evenly rounded at 
the apex as shown in figs. 1 and 2; but in a few it is much 
shortened, greatly elongated and with parallel sides, or quite 
triangular and acute at the apex. The middle and posterior 
tibia may be simple and untoothed as with the majority, or 
provided with an acute tooth at about the middle as was no 
doubt the ancestral condition. Other characters are also vari- 
able, but they are of less value for purposes of differentiation. 
The male genitalia have been carefully studied by Mr. Giffard. 
I have critically examined the mounted dissections which he 
made from various forms, together with his drawings, and 
can find no differentiating characters of moment, though there 
were noted minor modifications. These latter, I believe, are 
mainly due to the changes which have been produced in the 
parts by mounting rather than to any material difference in 
the structures themselves. The male genitalia do, however, 
show distinctive generic characters. Plate II, which is made 
from one of Mr. Giffard’s careful drawings, will give a good 
‘idea of the distinctive features, and enable anyone who wishes 
to contrast them with those found in other genera of the 
Lucanidae. 
Studying the specimens themselves in regard to the struc- 
EXPLANATION: OF PLATE... 
y. 1, Male of Apteroeyclus honoluluensis Waterhouse (typical form). 
Fig. 2, Female of Apterocyelus honoluluensis Waterhouse (typical form). 
3, Head of Apteroeyelus honoluluensis var. waterhousei Sharp (typi- 
cal). 
4, Head of Apterocyelus honoluluensis Waterhouse (atypical form). 
Fig. 5, Head of Apterocyclus honoluluensis var. palmatus n. var. 
6, Submentum, trapezoidal form. 
7, Submentum, simple or arcuate form. 
Fig. 8, Fore tibia, the multidentate form. 
Fig. 9, Fore tibia, a composite form. 
Fig. 10, Fore tibia, a simple or reduced form. 
Fig. 11, Fore tibia, the tripalmate form. 
Fig. 12, Rhyneogonus alternatus n. sp. 
. 
