THE CANADIAN ENTOMOLOGIST 99 



Meteorus dimidiatus Cress. (Teste Brues). 



Two generations per annum. Hil)ernate as larvae in overwintering cut- 

 worms, such as Etixoa tristicula Morr. Adults emerge in May, and parasitize 

 P. orthogonia and other Noctuidae. The female lays about twelve eggs in each 

 host. Our records of the date of appearance of the second generation adults 

 indicate a considerable variation from year to year, but the majority have emerg- 

 ed in July. 



On account, it is thought, of the underground habits of P. orthogonia the 

 percentage of infestation by this Braconid is never as high as it is in the Euxoas, 

 but it is of interest to note that we have bred it from Sidcmia devastator Brace, 

 a species of cutworm that has never been recorded as coming to the surface. 

 Gonia capitata DeGeer, and other Species. (Teste Tothill). 



At least two closely allied species of Tachinidae, with similar habits, are 

 included here. The only differences that we have been able to detect are slight 

 variations in larval and adult structures. We have found three types of stage 1 

 larvae. All of the species have one generation per annum. They hibernate as 

 puparia. The adult emerges in May, and lays thousands of minute eggs on vege- 

 tation. When eaten by cutworms these eggs hatch and the escaping larvae ma- 

 ture at about the time that the host pupates. They transform into the hiber- 

 nating puparium either in the soil, or in the dead larva or pupa of their host. 



The selection of vegetation by the fly. and the location of the eggs on 

 selected plants, plays an important role in the value of the parasite. 



We have found the most abundant oviposition on the blades of Blue-joint 

 {Agropyron Smithii.) though it is frequent on other native grasses, and to a 

 slightly less extent on imported graminae, including grain crops. Native dicoty- 

 ledons may carry a few eggs, but we have never found them on introduced plants 

 belonging to this class. 



Unfortunately P. orthogonia does not feed readily upon Blue-joint and 

 we did not find that G. capitata selected the lower portions of the plants for ovi- 

 position in preference to the upper. The high percentage of parasitism is rather 

 remarkable since P. orthogonia feeds almost entirely below the ground. It would 

 appear, however, that periods of drought are beneficial to this parasite since the 

 reduced growth of vegetation necessitates a more abundant oviposition on avail- 

 able plants. 

 Bonneta comta Wied. (Teste Tothill). 



Very little is known of the life history of this species. The adult appears 

 in July and August, and it belongs to the group of Tachinidae that are larvipar- 

 ous. It is probably, therefore, double brooded, though it has not been bred from 

 overwintering species of cutworms. Regarding the selection of plants for the 

 supposed larviposition the following figures, obtained in V)\5, are of interest. 



P. orthogonia larvae collected from Spring Wheat were 21% parasitized 



P. orthogonia larvae collected from Fall Wheat were 2% parasitized. 



P. orthogonia larvae collected from Alfalfa were 0% parasitized. 



This suggests a similar habit to that of Gonia capitata in the selection oi 

 plants. 



With a more complete knowledge of the habits of these parasites, particu- 



