PUP^E OF LADY-BIRD. 285 



flies make reprisals upon them for their destruction of 

 the helpless aphides. Swarnmerdam observed eight 

 of these parasites issue from one pupa of a Syrphus.* 



The lady-birds (CoccindlidcR) glue their pupae to 

 leaves in much the same manner with the flies just 

 mentioned: but their skin, instead of becoming smooth, 

 wrinkles up by the shortening of the body of the 

 grub; because it is not so soft and pliable, and 

 cannot, therefore, be compressed. The interior, how- 

 ever, is smooth. ^ 



Those insects which live during their first stages 

 in the water, exhibit a very different economy when 

 they change from larvae into nymphs, as may be 

 exemplified in the May-flies (Ephemeridce) and the 

 dragon- flies (Libellulina). But as these will require 

 to be described in a future page, we shall content our- 

 selves at present with an account of an interesting 

 but minute species of tipulidan gnat ( Corethra plu- 

 micorwis, MEIGEN), of a straw colour, whose history 

 was first given by Reaumur and De Geer. The 

 latter was induced, from the beautiful transparency 

 of the larva, to name it Tipula cristallina, a qua- 

 lity which renders it, its size being also very minute, 

 rather difficult to discover: it is however, a good 

 subject for microscopical observations. Taking ad- 

 vantage of the recent improvements in microscopes, 

 Dr Goring has accordingly given coloured figures 

 both of the larva and pupa, as observed by him, in 

 which he has added a few minute detailsj that are 

 not in the otherwise very accurate figures of R/au- 

 mur. 



The larva is rather less than a quarter of an inch 

 long, and somewhat resembles in form those of the 

 same family, particularly in the parts about the head, 



* Part ii, p. 99. t J. R. 



$ Goring and Prilchard's Nat. Hist., No. 1; and Reaumur, 

 vol. v., mera 1. 



