DESCRIPTION OF PLATE 



(frontispiece) 



Fig. I. Male fly {Chirononms dorsalis). x 8. 



Fig. 2. Female fly. x S. 



Fig. 3. Dorsal view of half-grown larva, x 8. 



Fig. 4. Side view of older larva. 



Fig. 5. Ventral view of pupa, x 8. 



Fig. 6. Side view of pupa, x 8. 



The full-grown larva of C. dorsalis is about 20 mm. long ; the fly 

 varies from 575 to 7-5 mm.; and the pupa is a little longer than 



the fly. 



