148 



[July, 



subsequently also later in the year. Occurs in various places where I 

 collect, and sometimes in fair numbers. 



Cilipes. — A. fairly common species, found sparino'ly in May and 

 Tune, and more frequently in the autumn, from August to October. 

 Whenever I catch sight, in a Plinra, of a very Inrge and bright yellow- 

 anal organ, narrow at the base and wide at the end, I at once think of 

 cilipes, and seldom, if ever, is one mistaken. Its close relationship to 

 lutea and scutellaris is shown by the strong tendency to a pale thorax, 

 the long loose hairs under the hind femora, the rather small and 

 shortly bristled palpi, and especially by the much diminished size of 

 the under pair of supra-antennal bristles, a condition very exceptional 

 in this group with bristly pleurae or bristly tibife, but the rule for the 

 most part in the one immediately to fol o\r, with bare pleurae and 

 cilialess tibiae. 



Lutea and scutellaris. — Both are moderately common ; lutea is 

 widely distributed, and so probably will scutellaris be found to be, now 

 that attention has been drawn to it. Perhaps no two species at first 

 sight, and in their typical colour forms, appear to be more dissimilar. 

 Each, however, varies in the direction of the other, lutea occasionally 

 acquiring a dark abdomen, and scutellaris a pale thorax. But even 

 then I think it is quite possible to discriminate them by colour alone 

 for the pale thorax of scutellaris is of a decidedly reddish hue, whilst 

 lutea's is essentially yellow, in fact the very same differences as are pre- 

 sented by their antennae. In structural characters they approach each 



other very nearly, and the resemblance 

 extends even to the male genitalia, 

 as is well shown in the accompany- 

 ing figures (lettering as in vielano- 

 cephala). Scutellaris (Fig. 4) is de- 

 picted in the active state, with the 

 small subanal body {d) exposed, and 

 d the pale yellow ventral plate (c) thrown 



^''"- 4- back nnd partially twisted round so as 



to expose its inner surface. Lufen, on the other hand, is represented 

 in the inactive state, with the black 

 ventral plate lying flat against the 

 under surface of the hypopygium 

 The only noticeable distinctions 

 here are the shorter and stouter 

 anal organ of scutellaris, and the 

 difference in the colours of the 

 ventral plate which is even more 



