374 The Ohio Naturalist. [Vol. XI, No. 8, 



TWO SPECIES OF DIPTERA OF THE GENUS DROSOPHILA. 



H. R. NiSWONGER. 



The minute flies of the genus Drosophila are especially abun- 

 dant about decomposing vegetables, and fermented fruit, around 

 €ider refuse, wine vats, vinegar, etc. ; attracted to these substances 

 for food and as places of oviposition, since the larvae live in 

 -decaying organic matter. The two species under consideration are 

 Drosophila busckii Coq. and Drosophila funebris Fab. 



The species of this genus arc of a dusty red, yellow or black, 

 .and somewhat plump appearance. The feathered or comb-like 

 .arista of the antennae, the distinct oral vibrissae, and the peculiar 

 venation of the wings are es]Dccially characteristic. The arista is 

 plumose or feathered on both sides mostly on the upper from the 

 middle on. The wings are longer than the abdomen, the distance 

 between the anterior and posterior cross-veins less than the third 

 segment of the fourth longitudinal vein. The second basal cell 

 is united with the discal cell and consequently seeming to be 

 .absent. The costa reaches to the fourth longitudinal vein. 



Drosophila busckii Coq. This species is recorded as reared 

 from rotten potatoes and from the burrows of "Chion cinctus" 

 one of the long-horned beetles whose larva tunnel in the solid 

 wood of hickory trees. The writer succeeded in having this spe- 

 cies oviposit in decayed fruit, but was unable to carry the life 

 history any farther than the egg stage. Decaying vegetables 

 seem to be the chief breeding places. The exact period of the 

 different stages was not determined, but about two weeks are 

 required for the develo]3mcnt from the egg to the adult. The 

 eggs are laid in the decaying matter and the entire larval period 

 is passed within this. About the time the larva enters the pupal 

 stage it leaves the decaying material and i)upates near by within 

 the old larval skin. The adult emerges in a few days. 



Description of insect: Egg, Fig. Ic. The egg is elongated in 

 fonn and white in color. Near the cephalic end are slender 

 appendages varying in number from three to five. The egg with 

 appendages is about five-tenths (.5) millimeters in length, and the 

 whole surface is ornamented with a net-like pattern. 



Larva. Fig. Id. The larva is a slender white maggot and when 

 full grown measures about four (4) millimeters in length. It is 

 widest near the middle and tapering toward each end, more 

 toward the cephalic end than the caudal. The main trachael 

 trunks are visible, the cephalic spiracle prominent, compound, 

 consisting of several, usually eight divisions, each division opening 

 separately. Fig. If. This compound spiracle may be exerted quite 

 a distance or may be withdrawn into the prothoracic segment. Two 

 ■caudal spiracles project prominently backward. Caudal segment 



