Miscellaneous . 393 



On the Pteromalince of the Hessian Fly, 

 By Prof. K. Lindeman. 



Prof, Lindeman has laid before the Society of Naturalists of 

 Moscow an interesting account of the Pteromaline parasites which 

 he has bred from puparia of the Hessian fly obtained from various 

 parts of Eussia. He contrasts the species observed by him with 

 those recorded by Eiley f in North America, as follows : — 



In North America. In Russia. 



1. Merisus destructor, Say. I 1. Merisus intermedius, Lind. 



2. subapterus, Hil. \ 2. Tetrastichus Rileyi, Lind. 



3. Tetrastichus productus, Itil. 3. Eupelmus Karschii, Lind. 



4. Eupelmus Allynii, Fi-e?ieh. 4. Platygaster minutus, Lind. 



5. Platygaster Herrickii, Pack. 5. Semiotellus nigripes, Lind. 



6. Euiyscapus saltator, Littd. 



7. Platygaster P sp. 



The Russian species ho tabulates as follows : — 



1. Winged. 



a. From one to four joints of the flagellum nar- 



rowly annular. 



• Flagellum nine-jointed Semiotellus ? nigripes. 



** Flagellum ten -jointed. 



a. Antennae with a distinctly two-jointed 



club Tetrastichus Rileyi. 



jS. Antennae not clavate. 



Flagellum with one annular joint Eupelmus Karschii. 



Flagellum with two annidar joints .... Merisus intertnedius. 



b. No narrowly granular joints in the flagellum Platygaster minutus. 



f> iTT-i-i J- J. • \ -Merisus inter medius. 



2. With rudimentary wmtfs < . "='*"*•>, 



•' ^ j var. microptera. 



3. Wingless Ewyscaims saltator. 



Merisus intermedins is so called because it appears to be interme- 

 diate between the two American species M. destructor and suh- 

 ajiterus, which were formerly regarded as forming one species. Its 

 colour is metallic green : the antennae of the male yellow, of the 

 female brown ; legs yellow, with the eoxse, and sometimes also the 

 femora, black ; under surface of abdomen often reddish brown, espe- 

 cially at base. Both male and female may have stunted wings, but 

 these are longer than in M. subapterus, and show venation. Length 

 2 millim. The species appears to be very abundant in all parts of 

 Russia, and seems to have two generations in the course of the 

 summer. 



Tetrastichus Rileyi is rather less than 2 millim. long ; black, with 

 a blue or green lustre. Antennae blackish brown ; legs yellow, with 

 the tips of the tarsi dark ; abdominal segments densely hairy, 

 especially towards the apex. Tetrastichus productus is regarded by 

 Riley as a parasite of Merisus ; the author has been unable to arrive 



t " On the Parasites of the Hessian Fly," in Proc. IT. S. National 

 Museum, vol. viii. (1885) p. 413. 



