SOME OTHER FLIES 19 



Anthomyidcv, whilst the true blue-bottles belong to 

 the Muscidce, and the grey blow-flies to a section 

 (Sarcopkagina) of the Tachinidce. 



There are some other outdoor flies which are not 

 very dissimilar to the common blue-bottle, but they 

 are more soberly coloured, ranging from bluish black 

 to speckled and tinted greys; some of these have a 

 pattern on the shiny upper surface of the abdomen 

 which is conspicuously and beautifully chequered. 

 Closely akin to these latter is the large grey blow-fly, 

 or flesh-fly, Sarcophaga carnaria ; it is much referred 

 to in entomological books as of marvellous fecundity. 

 The female deposits not eggs in a few hundreds, but 

 already hatched maggots to the number of many 

 thousands. Amongst half-a-dozen rarer kinds of 

 smaller grey blow-flies the females differ in their 

 striped markings, but their respective males seem quite 

 indistinguishable apart. 



Notwithstanding the prodigious fecundity of the 

 grey blow-fly, the credit of being a practically useful 

 scavenger of carrion must be given only to the blue- 

 bottle, which is of a more robust habit, and which so 

 promptly monopolises available matter that Sarco- 

 phaga carnaria and her congeners are sometimes, 

 perforce, compelled to give their larvae a mere vege- 

 tarian diet. 



The yellow 7 cow-dung fly, Scatopkaga stercoraria, is 

 inoffensive, and one of the commonest flies observable 

 in the course of a country-side ramble. It and its 

 congeners are distinct in habits and appearance from 

 any of the other flies above-mentioned. In this species 

 the male is larger than the rather more smooth and 



