DR. F. LEUTHNER ON THE ODONTOLABINI, 409 
and N. saundersi (fig. 13), the largest species of Neolucanus, would be bridged over in 
a very unexpected manner. ‘The females of the two latter species (figs. 9, 11, 12) are 
so variable that it is not easy to separate them, though the males are more easily 
distinguishable. In WV. Jama the mandibles are always priodont in small males, but they 
are forked at the tip in larger ones. In WV. sawndersi they are more developed. The 
priodont form (fig. 16) much resembles that of V.lamaé. In rather larger specimens 
a gap appears in the middle, and an amphiodont form is thus developed. The basal 
teeth, traces of which are visible on both sides in fig. 13 (Parry’s type), are absent in an- 
other specimen in the British Museum, only the apical teeth remaining. Oddly enough, 
in large specimens an upright tooth is developed at the base of the mandibles!, which 
is indicated as a mere rudiment in the smaller priodont forms. 
N. championi (fig. 83, fig. 62), NW. sinicus (fig. 73, fig. 52), and N. oberthiiri 
exhibit only unimportant differences in size and shape, and are chiefly distinguished by 
their colour. 
The large species of Veolucanus lead us, without any very wide interval, to the first 
section of the genus Odontolabis, Hope. 
1. Odontolabis. 
In this genus, 0. siva, Hope, and its allies exhibit the least divergences in the females. 
Their resemblance to the last species of Neolucanus is very remarkable; they are found 
in the same localities, and are very easy to mistake for one another. But the similarity 
of the small males (Pl. LXXXVI. fig. 6, and Pl. LXXXYV. fig. 15) is not without 
significance, as it has led experienced coleopterists to treat O. siva and WV. lama as 
one species! ‘The similarity in form and colour between certain parallel species of 
Neolucanus and Odontolabis, which inhabit similar localities, is so great that we are 
sometimes reminded of the well-known cases of true mimicry in Lepidoptera noticed 
by Bates and Wallace. 
1 The intelligent observer will ask why this genus should develope so remarkable a structure (so similar to 
the genus Prismognathus, Motsch.), which one would think would not be developed, owing to mechanical 
obstacles. But we shall find the explanation in a direction where we should least have expected it. The 
female mandibles are flattened, and the right mandible, when closed, partly overlaps the left. heir structure 
allows them to expand yery widely, and the concavity behind the inner teeth exactly corresponds to the 
rounded epistoma-like clypeus (Pl. LX XXIV. fig. 16, Pl. LX XXY. fig.9). At the point of the upper surface 
where the right mandible overlaps the left, we frequently find a projection which prevents their further closing. 
The length and thickness of the male mandibles render it impossible for them to overlap, except at the tip, 
and the pressure of the mandibles may have given rise to a projection which gradually developed into a large 
tooth, which would be produced on the opposite side by the law of bilateral symmetry. The base of the 
mandibles is exposed to similar friction, where the upper side touches the frontal margin (apart from the 
probability of the mandibles being also used for protection when the animals are fighting). Rudiments of 
these teeth are found in the males of IV, swinhowi (P]. LX XXIV. fig. 15) and other species. 
VoL. XI.—Part xI. No. 4.—November, 1885. 3P 
