DIPTERA. 243 



As it will be seen, I have commenced with the 

 Psychodidae, because they bear the strongest resem- 

 blance to the Lepidoptera ; and concluded with the 

 CE strides and Hippoboscidae, as the former have no 

 proboscis, and the latter have been made into a 

 separate order, or suborder. 



Some of the larvae of the Tipulidae are Fungi-feeders, 

 as are also those of the Mycetophilidae, Phoridae, 

 Platypezidae, Drosophilidae, and Helomyzidse. The 

 larvae of the Cecidomyidse and the Trypetidse are 

 gall-makers'. 



The parasitic larvse are of two kinds, viz., external 

 and internal. Among the former are those of the 

 Bombylidse, Syrphidse, and Conopidae; among the 

 latter are those of the Tachinidse, which breed inside 

 the pupse of other insects, and of the (E strides, which 

 attack animals. 



The Empinse prey on other insects in the perfect 

 state. The Hippoboscidae feed on the substance at 

 the roots of the hair and feathers of animals and birds. 

 The flies which suck the blood of man and animals 

 belong to the genera Culex, Ceratopogon, Chrysops, 

 Tabanus, Hsematopota, and Stomoxys. 



Some of the species of the genus Chironomus are 

 only to be obtained in the winter, as are all of the 

 genus Trichocera, which may be seen, even when the 

 snow is on the ground, dancing up and down in the 

 sunshine. Several of the order may be obtained all 

 the year round. Some species of the genera 



