8 MISC. PUBLICATION 174, U.S. DEPT. OF AGRICULTURE 



Government of Vladimir, and in the Province of the Don Cossacks. 

 In the United States National Museum collection are three specimens 

 labeled " Plasty g aster minutus Lindeman, Russia " which it is be- 

 lieved were sent to Riley or Howard by Lindeman himself and which 

 are probably paratypes of Lindeman's species. These differ in no 

 way from the North American hiemalis Forbes. Lindeman gave the 

 length of his species as 0.5 mm, which is somewhat smaller than the 

 smallest specimens of hiemalis; but, in view of the fact that the sup- 

 posed paratypes are fully as large as typical examples of hiemalis, it 

 is believed that this measurement was in error. In other respects 

 Lindeman's short description of minutus, as also his statement that 

 as many as 11 specimens of the parasite sometimes emerge from the 

 same fly puparium, applies to hiemalis, and it appears certain that 

 the two names refer to the same species. The name minutus was 

 proposed in 1887, 1 year earlier than hiemalis, but the former name 

 had already been used by Zetterstedt in 1838 for a different species, a 

 fact which Lindeman overlooked. Dalla Torre proposed the name 

 minutula, in 1898, for minutus Lindeman, not Zetterstedt, but this, 

 as well as minutus Lindeman, must fall as a synonym of hiemalis 

 Forbes. 



This species was transferred to the genus Polygnotus by Riley, and 

 much of the literature regarding the species treats of it under the 

 name Polygnotus hiemalis, but in 1924 Fouts synonymized Poly- 

 gnotus with Platyg aster, thus restoring the species to its original 

 genus. 



European records of this species are apparently not very numerous 

 and, in some instances at least, the species has been confused with 

 zosine. There can be little doubt that the references by Enock in 

 1891 to the presence of Platygaster minutus in England refer to P. 

 hiemalis. Specimens mounted by Enock and labeled minutus, but 

 without indication of locality, are in the United States National 

 Museum collection and differ in no way from typical hiemalis. There 

 is also one specimen of this species reared from the hessian fly by 

 O. E. Janson in England in 1887. 



Another specimen in the National Museum collection was reared 

 from the hessian fly by F. Cohn, Breslau, Germany. This specimen 

 was sent to Riley by Professor Cohn during the course of their 

 correspondence regarding the fly. It is poorly mounted on a slide, 

 but its characters, so far as they can be ascertained, agree with those 

 of hiemalis. 



Two other specimens of hiemalis in the collection were reared from 

 the fly by T. Cheviroff, Leningrad (St. Petersburg), Russia. No 

 literature reference to these specimens is known to the writer. 



In 1900 W. Pospjelov published a- paper on the parasites of the 

 hessian fly in Russia, in which he redescribecl Polygnotus minutus 

 and figured the antenna together with a cluster of cocoons. These 

 figures seem to agree with those of hiemalis, as does also the descrip- 

 tion, but the latter might also apply to many other species of Platy- 

 gaster. Pospjelov's statements that the larvae accomplish their de- 

 velopment during the summer, pupate in the fall, and emerge as 

 flies in the spring, after overwintering in the cocoons, seem to agree 

 more closely with the known facts in the development of zosine than 

 with those of hiemalis. It is not impossible that both species were 



