l90l.] 



223 



arriving at satisfactory conclusions as to the value of the various 



forms which have been placed under 

 this name and that of H. jyarvulus, 

 and Mr. McLachlan has already 

 noticed the uncertainty which exists 

 as to the real importance of these 

 forms (Trans. Ent. Soc. Lond., 1S9S, 

 p. 164). As he has so recently 

 failed to dispel the obscurity sur- 

 rounding this question, it would be 

 superfluous on my part to attempt 

 to do so, and we must accordingly 

 await the accumulation of further 

 observations and material. Figures 

 of the (^ appendages, drawn from 

 examples of varying appearance 

 and from different localities (Mout- 

 pellier, the Pyrenees, and Algeria) 

 do not help to solve the problem. 

 A good sei'ies from each of many 

 and widely separated localities is 

 to be desired, but unfortunately 

 these particular insects seem to 

 occur for the most part singly. 



I propose therefore, in the mean- 

 time, to deal with group II. It 

 contains two very closely allied 

 species ; nevertheless, in good and 

 well marked specimens of M. incon- 

 spicuus and U . pcllucidus, no difficulty exists in their determination. 

 The former has the wings with a more or less fuscous tinge, while in 

 pelhicidiis they are greyish, and the gradate nervules are frequently 

 clouded, which they never are in inconspicuus. But in old examples, 

 and in others which are teneral in condition or ill-marked, the deter- 

 mination is not so easy, and the genital characters of the (^ are 

 useful aids. 



The principal differences may be tabulated thus : — 



H. INCONSPICUUS. 



Wings with a fuscous tinge, with some 



resemblance to those of Sisyra fuscata 

 in fully matured specimens. Nervures 

 unclouded. 



H. PELLUCIDUS. 



Wings greyish, in well marked ex- 

 amples with distinct cloudings about 

 the gradate nervules. 



X 2 



