SPECIES OF THE GEXUS MUSCA, LIXXAEUS, 415 



vaccine scarifications, on the bellies of calves. Since then, in collaboration with 

 Major Cragg, I. M.S., I have described several other Indian species that have a similar 

 habit. Looked at with the naked eye, the species of this group closely resemble Musca 

 domestica. I have never seen a single specimen of any of these species caught in the 

 bazaars in India, and with the single exception of Miisca Immilis, they are found only 

 on animals, sitting about on plants, and on cow-dung. They are all necessarily 

 intermittent feeders, and flit about from one animal to another, never staying long 

 at one spot ; and herein lies their importance as the possible carriers of trypanosomes 

 such as those which cause nagana and surra. I would, therefore, particularly like 

 to draw the attention of veterinary officers practising in the tropics to these 

 haematophagous species of the genus Musca. They abound in all tropical countries, 

 and specimens can always be caught on animals, as well as on dead game. 



All the Indian species I have studied breed in cow-dung, either when it is dropped 

 in the fields, or when piled up in heaps around cowsheds, etc. The larvae of all 

 the species in any given locality can be easily collected by scooping up patches of 

 cow-dung about .24 hours old, and placing it on earth in a tin tray with sides up 

 which the larvae cannot crawl. There is no need to disturb the dung, but the tray 

 should be placed in the sun every day, and the earth at the sides of the tray 

 regularly examined for pupating larvae. Such larvae are of a characteristic creamy 

 white colour, and do not contain any food. They should be collected, some pre- 

 served as noted above, and the remainder allowed to pupate in earth in a cigarette 

 tin. The puparia should be dealt with as noted above, always remembering to pin 

 the puparium of each specimen under it. The mature larvae of most of the species 

 leave the dung to pupate, but others may stay just under it, so that it is necessary 

 towards the end of the observation to turn over the dung and examine it for puparia. 

 The puparia of several of these species are almost white, while^others are of a greyish 

 colour. 



The Oriextal Species. 



In addition to the specimens from this region in the National Collection, I have 

 re-examined my own extensive collection consisting of about 2,500 specimens, the 

 majority of which have been bred from larvae, most of the species being represented 

 by long series in perfect preservation. I am able then to note the variations in external 

 characters, a point of considerable importance in determining an atypical specimen ; 

 and anyone who has examined many species of this genus will have noted the great 

 difficulty often experienced in giving a name to an odd specimen which is in some 

 respects atypical, or greasy. I also have a long series of bazaar flies collected from 

 all the larger towns in North India. 



In these notes I propose recording my preliminary studies of the Oriental species, 

 but it should be understood that as more material becomes available for macroscopic 

 and microscopic study, it may be necessary to revise any previous conclusion, so 

 that these notes must not be considered to represent the final revision of the Oriental 

 species, but rather a preliminary contribution in that direction. In collaboration 

 with Mr. Senior- White, I am now preparing a paper in which all the Oriental species 

 will be described and illustrated ; we hope to be able to include in it a simple yet 

 accurate key for the determination of these species. 



1. Musca nebulo, Fabricius. 



Synonyms : Musca determinata, Walker. 

 ? Musca multispina, Awati. 



In 1910, Major Austen determined the common Madras house-fly for me as Musca 

 nebulo, and since then I have always referred to this species under that name. 

 Fabricius, in his short and wholly inadequate description of this species, states that 

 the type, a female, is from " India Orientalis," and was given him by Professor 



