126 DRAGON FLIES VS. ISIOSQUITOES. 



other species in act of oviposition, the females were al- 

 ways destitute of the male, and only in one instance I 

 saw a male retain its hold to the female while laying eggs. 

 The egg of Libellnla auripennis is irregularly oval, with 

 very fine granulations, sordid white and semitranslucent, 

 becoming amber yellow before the young larvse emerges. 

 Length, one-third millimetre; width, one-fourth milli- 

 metre. A number of eggs which were laid on July 23d, 

 at 6.30 P. M., disclosed the young larvae on August 1st. 

 The egg of Libellnla pulchella is very similar to that of 

 L. auripennis, in flict cannot be distinguished from it, ex- 

 cept that it is a little more irregular in shape. Length, 

 one-third millimetre ; width, one-fourth millimetre. Laid 

 July 23d at 6 P. JSI. ; young larvae emerged August 31st. 

 The mode of oviposition of Plathemis (P. trimaculata) 

 and Diplax (D. berenice and B. rubicundula) is identical 

 with that of Libellnla. The egg of the former is ellipti- 

 cal or subelliptical, granulated, semitranslucent, pale yel- 

 lowish white, becoming amber yellow before hatching. 

 Length, one-half millimetre ; width, one-third millimetre. 

 Laid July 13th, at 5 P. M.; young larvse emerged July 

 23d. The eggs of the two latter species are oval, yel- 

 lowish white, semitranslucent, and slightly granulated. 

 Length, one-half millimetre; width, three-tenths milli- 

 metre. Laid August 12th ; young larvse emerged August 

 22d. 



Calopteryx (C. virgo) deposits her eggs on the under 

 side of leaves of aquatic plants. (Brandt, iNIem. Ac. Sc. 

 St. Petersb., 1868.) 



The habits of Agrion and Lestes differ entirely from 

 that of Libellnla. They deposit their eggs in a groove 

 made by their ovipositors along the stems of Avater plants. 



