On the Malacoderm Genera Prionocerus and Idgia, 325 
XXXIII.—The Malacoderm Genera Prionocerus and Idgia, 
and their Sexual Characters [Coleoptera]. By G. C. 
Cuampion, F.Z.S. 
[Plates XI. & XII.] 
Tuts paper is based upon a study of the species of Priono- 
cerus, Perty, and Jdgia, Cast., contained in the National 
Collection at S. Kensington, in the Hope collection at 
Oxford, and in that of Mr. H. E. Andrewes, the last-named 
being rich in Indian forms *, including types or co-types of 
various insects determined by Bourgeois and Gorham. The 
British Museum material includes the types of three Indian 
species belonging to the genus Idgia—Cantharis melano- 
cephala, Fabr., Telephorus assimilis, Hope, and Thaccona 
dimelena, Walk.—which have been omitted from or are 
wrongly placed in our catalogues; many interesting 
Malayan forms captured by Mr. Doherty or Mr. G. E. 
Bryant ; and very extensive series of several species from 
the highlands of Eastern and Central Africa. ‘The two 
genera here studied, which Lacordaire, Redtenbacher, and 
Bourgeois were inclined to treat as one, are restricted to 
Africa and Asia; and upwards of sixty species have been 
described as belonging to them, about half of these having 
been named during recent years by Pic. 
The sexual characters of the forms enumerated in this 
paper are described in detail, important tarsal and other 
structures having been apparently overlooked by all writers 
on these insects, including Bourgeois, who has given a good 
deal of attention to the subject. Another mark of dis- 
tinction, unnoticed in our text-books, and common to the 
two sexes, is the single spur to the anterior tibie, the 
absence of the second spur being characteristic of the 
(idemerid genera Nacerdes and Xanthochroa, the species of 
which bear a superficial resemblance to many Jdyie. The 
males of Prionocerus and Jdgia have, in common, a closely, 
regularly pectinate, black comb along the inner edge of 
joints 1-3 of the anterior tarsi, which is quite conspicuous 
in the yellow-legged forms+. A similarly pectinate comb 
* The types of the new species described from his collection and a 
selection of the others have been presented by Mr. Andrewes to the 
Museum. k , 
t+ The males of one or two Lampyrids allied to Phengodes havea 
row of scattered teeth on the first joint. 
Ann, & Mag. N. Hist. Ser. 9. Vol. iii. 22 
