394 Mr. G. J. Arrow on Rutelid Coleoptera. 
same position. These two species are otherwise scarcely 
distinguishable. 
The Kast-African A. punctipennis, Fahr., another species 
of almost identical appearance, may be distinguished from 
those just referred to by the entire absence in both sexes of 
any armature of this kind. In a former paper dealing with 
Rutelid Coleoptera from the Transvaal (Ann. & Mag. Nat. 
Hist. (7) iv. p. 120), regarding all the unarmed specimens 
as females, I failed to distinguish these two species, and 
referred a specimen of A. punctipennis to the West-African 
species. The range of these insects is therefore still less 
wide than I there stated. dA. punctipennis, Fahr., though 
distinct from A. hirtellus, Lap. (=cinerarius, Burm.), is, I 
believe, identical with A. cephalotes, Gerst. 
In all these forms the two sexes are closely similar and the 
appearance of both that of typical Adoret’; but there are 
members of the group in which the male characters are 
greatly exaggerated, the hind legs being of enormous size 
and the characteristic appearance of the true Adoretus almost 
lost. One of these is A. albosetosus, Waterh. (which has been 
twice redescribed by M. Fairmaire under the names of a/bo- 
hispidus and hystrix). For this a new genus will have ulti- 
mately to be formed, but I do not propose to do this at present, 
as I have not yet been able to see the female, which appears 
to be much rarer than the male. 
An East-African insect not very distantly related to the 
last has been described by Herr Brenske under the name of 
Trigonochilus coriaceus. ‘The author was evidently not 
acquainted with the nearest allies of this remarkable beetle, 
for he has formed a new subfamily for it. Had the female 
only been known, however, the species would no doubt have 
been placed in the genus Adoretus, the peculiarities which 
have induced its separation virtually all resulting from the 
great developments peculiar to the male. Here again there 
is a strong spine upon the lower edge of the hind femur, 
which, with the tibia, is greatly enlarged, asin A. albosetosus. 
In the British Museum is an undescribed species from 
Angola, which, although differing considerably in general 
appearance from J’, cortzaceus, may well be placed in the same 
genus. The two sexes of this show similar remarkable 
differences. 
Trigonochilus politus, sp. n. 
Breviter ovatus, nitidus, rufo-testaceus; capite rugoso-punctato ; 
prothorace parvo, lateribus valde arcuatis, longe flavo-hirtis, 
marginibus reflexis, angulis posticis rotundatis, disco fere polito ; 
