451 



NOTES ON THE LIFE-HISTORY OF THE TACHINID 

 FLY, PHOROGERA SERRIVENTRIS, RON DAN I, AND 

 ON THE VIVIPAROUS HABIT OF OTHER DIPTERA. 



By W. Wesche, F.RM.S. 

 {Bead October 26th, 1909.) 



Plate 3G. 



In 1906 I figured and described the remarkable ovipositor of 

 this fly.* I could not explain nor understand its use, and in 

 January 1908 I mentioned the biological problems presented 

 by its morphology and surroundings.! At Mersea Island, on 

 the Essex coast, during the past summer I was able to capture 

 and watch a certain number of this species; they were never 

 very plentiful, and are difficult to recognise, as they behave 

 in a similar manner to a number of flies of about the same 

 size, and their general appearance is much like that of a 

 number of other Tachinidae, which also have very hairy eyes,, 

 are greyish black with white shimmer, and are clothed with 

 many strong spines ; consequently, till the insect was captured 

 and examined with a lens, it was impossible to be certain that 

 it was not Blepharidea, Plagia, Frontina, or one of the smaller 

 Sarcophaga. 



It was usually seen quietly resting on a leaf, often that of 

 a bramble (Rub us fruticosus) which formed part of a hedge 

 that was my habitual hunting-ground. Judging by my captures 



* Genitalia of Diptera, W. Wesche, Trait*. Linn. Soc. Ser. II. Zool. 

 vol. ix. p. 364, 1906. 



t Jour. B. Me. Soc. 1908, pp. 421-2. 



