MUSCID/E. 339 



ordinary numbers, many miles from the nearest human 

 habitation. Either their eggs or the newly hatched larvae 

 are deposited upon meats, and only a day or two is suffi- 

 cient to transform the material into a creeping mass of 

 disgusting maggots. The larvae of species of this genus 

 sometimes have habits similar to those of the screw- 

 worm flies. «The blue-bottle and green-bottle flies have 

 habits identical with those of Calliphora, but they are not 

 so common. The screw-worm fly ( Chrysomyia macellaria ) , 

 an insect common over nearly all of North and South 

 America, is bright shining green or golden green in 

 color, but will be distinguished from the blue-bottles by 

 the presence of blackish stripes on the thorax. It depos- 

 its eggs, which hatch almost immediately, in decompos- 

 ing matter, as do other members of the family, but it will 

 also lay them in the ulcers of cattle, or wounds, or at 

 the orifice of the human nose, especially when attracted 

 thereto by a fetid breath. The larvae in these cases 

 quickly penetrate within the nasal and frontal sinuses, 

 sometimes to the number of a hundred or more, quickly 

 producing fever, extended ulceration and in frequent 

 cases, death. These cases of Myiasis, as the affection is 

 called, are not very frequent in North America, but have 

 been not seldom recorded from South America. Sarco- 

 phila Wohlfahrti, a European species, has similar habits. 

 The group Stomoxyinae includes about thirty known 

 species, all blood-sucking in habit, among which are the 

 notorious stable-flies, horn-flies and tsetse flies. The 

 horn-fly {Hcematobia serrata*) is a comparatively recent 



* Speiser, and, following him, Bezzi would call this genus Siphona, 

 a name hitherto applied to a genus of proboscideous Tachinidse, claim- 

 ing that the type was H. serrata (irritans); but I quite agree with 

 Austen that the case is by no means proven, and, even if it were, I do 

 not think it calls for such a revolutionary change in these long estab- 

 lished names. 



