1897] 31 



the upper part, and leaving behind it separated brown fibres. "When 

 it meets with the uppermost knot, or before meeting with it, it under- 

 goes its change to pupa, which turns upward, so that the flj which 

 will escape from the cephalic extremity may find an exit. I have 

 found as many as four or five pupae in the same terminal stem, some 

 lying in its axis, but most of them placed in the sheaths of the leaves. 

 When the perfect insect emerges, and before it has expanded its 

 wings, it creeps between the sheaths, in order to escape at the superior 

 extremity. It sometimes happens, therefore, that the sheaths, being 

 contracted by drying, press close against the axis, and all means of 

 exit being prevented, the insect perishes without being able to escape. 



The maggot is distinguished from that of Chlorops by the two 

 large stigmatical prominences at its posterior extremity, which, seen 

 from above, have a very characteristic form, reminding one of a hatchet. 

 The pupa presents the same characters, and at its anterior extremity 

 are two little cephalic horns furnished with several nodosities nearly 

 as in Oscinia. 



The wheat stems from which I reared Camarofa flavitarsis during 

 1894 came from the Departements of Haute Garonne and Tarn. 

 They also furnished a pretty large number of another interesting fly, 

 JElachiptera cornuta, Meig. 



Paris : December 30th, 1896. 



HINTS ON COLLECTINO ACULEATE HYMENOPTERA. 

 BY EDWAED SA.UNI)EES, F.L.S. 



It has been suggested to me that a few remarks on the above 

 subject would be of interest to some of the readers of this Magazine, 

 and therefore I will try and give some of my own experiences in the 

 matter and hope they may possibly be useful to others. It is 

 eminently a healthy occupation, as it is on fine, sunshiny days in 

 spring, summer and autumn that the best results are to be obtained; 

 dull, hot days in summer and early autumn are not to be despised, 

 but dull days in early spring and late autumn are practically useless, 

 and of course wet ones are so at any time. The Aculeates seem to 

 have a very keen perception of the atmospheric conditions, as I have 

 occasionally observed that on apparently fine mornings there are 

 scarcely any Hymenoptera about, and that when this is so, clouds 

 usually come up rapidly and the day is useless for the purposes of 

 collecting these insects. Aculeates are not early risers, nor do they 



