418 MAJOR W. S. PATTOX. 



Mitsca himiilis is very widely distn]:)uted, probably more so than any other 

 species of the genus. I have seen specimens from many parts of Africa, Palestine, 

 Mesopotamia, Persia, and from the whole of India to China in the East. 



The ]ate Professor Stein examined Wiedemann's type of humilis, as well as 

 Tliomson's types of angusiifrons and biviltatn, and says all three are the same species. 

 Until I can for myself examine these types I accept this determination. 



I have examined Walker's type of Miisca condttcens, a male collected b}^ Wallace 

 at Macassar, Celebes ; it is in good condition and is a small example of M. humilis. 

 Walker's type of M. praecox, a headless male from Ceram, Malasia, is exactly similar, 

 and is also a small specimen of M . humilis. Walker's type of j\I . primitiva, a female 

 from Fu-chau-fu, South China, is a typical specimen of M. humilis. 



Bigot's collection of Musca, fifty-three specimens, contains six males of his Musca 

 eutaeniata from " the Indies," chiefly from Pondichery and Cochin China, all of 

 which are rather small, but typical specimens of M . humilis. It will be remembered 

 that Brauer examined these specimens, and came to the conclusion that like eight 

 of the other specimens of Musca in Bigot's collection (Brauer 's numbers 257 to 265, 

 inclusive) they were "Mitsca ead.n. (wie die ersten 9 wohl domestica)." It is quite 

 clear from this that Brauer had a very vague knowledge of the species of the genus 

 Musca, otherwise he would never have called these six specimens of M. humilis 

 {eutaeniata), domestica. This is a warning not to accept the determination of types 

 by others as final without oneself examining them. Stein states that M. niveisquama, 

 Thomson, is identical with M. domestica, L. Major Austen has, however, drawn 

 my attention to Thomson's description of this species, in which he clearly states 

 that niveisquama is similar to his angnstifrons , and has two black thoracic stripes. 

 It is quite possible that niveisquama is Musca pitmila, Macquart. 



Awati gives angustifrons as a synonym for his Musca promi sea, and liis description 

 of this species makes it quite clear that it is M. humilis. This author, when describing 

 the three species, Musca nebula {multispina) , M. domestica atypical (divaricata) , and 

 M. humilis {promisca) , states that in the case of nebulo there are " two or more spines 

 on the humeral vein which may be present on both wings or on one of them only ; " 

 in the case of M. domestica atypical {divaricata), he saj^s there is " only one spine on 

 the humeral vein," and in M. Jiumilis also only one spine on this vein. In his 

 remarks at the end of the description of M. divaricata he sa3's : " There are always 

 more than one spine on the humeral vein in Musca multispina, whereas in Musca 

 divaricata there are never more than one." By the humeral vein Awati evidently 

 refers to the large basal root vein from which arise the subcostal and radial (subcostal ; 

 1st longitudinal) veins just before the small humeral transverse vein joins this root 

 vein to the costal. In all the species of Musca which I have examined, there 

 are always one or more small curved bristles situated on the inner side of the vein. 

 I have made a careful examination of the number of bristles present on the veins of 

 hundreds of specimens of Musca nebulo, M. domestica (at^'pical) and M. humilis, and 

 in a long series of domestica (atypical) in the National Collection a large percentage 

 had two bristles on the right root vein, and onl}' one on the left ; a few, on the other 

 hand, had two on the left vein and only one on the right. The majority, however, 

 liad only one bristle on each vein. In the case of a long series of nebulo, I find that 

 a few have two bristles on the left vein and one on the right, while some have two 

 on the right and only one on the left. But, and this is important in view of Awati's 

 statement that in this species there are always two bristles on this root vein on both 

 sides, I find that the majority of the specimens of nebido only have one bristle on 

 each root vein ; this also applies to Jiumilis. 



Musca humilis can always be recognised by noting that it is a much greyer fly 

 than the two others noted above ; that in the female the black thoracic stripes are 

 united behind the suture, forming one broad stripe, but are separated in front of 

 the suture ; in the male the stripes on each side have coalesced to foim one broad 



