88 ENTOMOLOGICAL NEWS. [June, 



becomes hardened, is likewise cast off, or moulted, and succeeded 

 by others, varying in number in different species of insects. Very 

 often there are changes in the shape, color, etc. , of the larva after 

 successive moults. 



Technical names for the process of moulting are ecdysis and 

 exuviation, and for the moulted skins, exuvice. 



In the case of those insects passing through a complete trans- 

 formation, when the larva moults for the last time, it becomes a 

 pupa, usually of quite dissimilar shape from the larva, and usually 

 quiet, that is, does not move from place to place. The last moult 

 of the insect's life is when the cuticle of the pupa splits open and 

 the imago emerges, and, after a short period, spreads its wings 

 and begins its aerial life. 



Where the insect undergoes but an incomplete transformation, 

 when the nymph moults for the last time, the imago state is en- 

 tered at once. 



Hitherto, in speaking of the segmented form of an insect's 

 body, reference has been made solely to the body-wall. So far 

 as the internal organs are concerned, the muscles, the nervous, 

 circulatory and respiratory systems, at least, are more or less 

 arranged in correspondence with the segmentation of the body- 

 wall. P. P. C. 

 o 



"SPORTS" IN VENATION. 



BY A. B. CORDLEV. 



Some time ago while studying the Hymenoptera collected 

 during the seasons of 1888 and 1889, I found three specimens 

 which puzzled me very much. They apparently belonged to the 

 genus Nomada, but differed from all the specimens of that genus 

 in our collection in that the anterior wings had but two submar- 

 ginal cells. I sent one of the specimens for determination to Mr. 

 E. T. Cresson, who replied as follows : " The bee you sent is one 

 of the varieties of Nomada tnaculata Cress. , a very variable spe- 

 cies. I have seen specimens in which the first transverse cubital 

 nervure was obliterated in one anterior wing, but not in both as 

 in the specimen you sent. Are these nervures absent in both 

 wings in the specimens you have? If so it is both curious and 

 interesting. Such ' sports' occur frequently among the Saw-flies, 

 but rarely among bees. ' ' On referring to the specimens retained 



