some new Species of Sagra, ^c. 237 



tibiae to agree exactly with Lacordaire's description ; in all the 

 rest there are rudiments, more or less distinct, of a sub-apical 

 tooth on the inner edge. The species is most commonly sent 

 from Java, but I possess it also from Nepaul, and it has been 

 taken by M. Mouhot in Siam, the specimen being in Mr. Saun- 

 ders's Collection ; in the British Museum is a small female from 

 Tenasserim. 



Sag7-a perlucida, Lacord. 



I consider, for the reasons stated below, this insect to be a 

 variety of Sagra Buquetii; M. Lacordaire has subdivided his first 

 division of the genus into three sections, the characters for which 

 are drawn from the toothing of the apex of the posterior tibiae in 

 the males; thus, in section A., the hinder tibiae have this part of 

 the limb tridentate ; in section B. the internal tooth is obsolete, 

 whilst the outer one is produced into a strong spine ; and in 

 section C, the one in which *S'. perlucida is placed, the tibiee are 

 simple and unarmed in either sex. The insects contained in this 

 section resemble, in a most remarkable manner, corresponding 

 species in one or other of the two preceding subdivisions, differing 

 merely in their somewhat smaller size, in the lesser development 

 of the hinder thigh, with sometimes a slight modification of its 

 under surface, and in the absence of the lateral teetli on the pos- 

 terior tibiae. The possession of an interesting series of aS*. nigrita, 

 in which the teeth dwindle away until they become nearly obsolete, 

 first led me to suspect that the above insects were males in which 

 an arrest of development of the posterior legs had taken place, 

 and that their typical forms belonged to the preceding sections. 

 After a careful examination of S. ignita, Weheri and others, I was 

 fully confirmed in this opinion, and in the present paper I have 

 placed these insects as varieties under the respective species to 

 which I consider them to belong ; at the time M. Lacordaire 

 wrote, he had, in most instances, so limited a number of specimens 

 under examination, that it was impossible to avoid separating 

 insects with such an apparent difference of structure, unconnected 

 by any intermediate link. An analogous instance may be adduced 

 in the case of Lucanus cervus, where the development of the male 

 mandibles varies so greatly in different individuals, as to have 

 caused the extreme states to be described under separate names. 



I have never seen an insect answering exactly to the description, 

 as given by Lacordaire, of S. perlucida, but 1 possess small in- 

 dividuals of S. Buquetii, S , in my own cabinet, in which the sub- 

 apical teeth are reduced to less than half their usual size. 



