140 



on the inner side of the small, externally chitinised labella, which 

 are everted for the purpose. In Stygeromyia, and also in Hcematobia 

 (a genus which occurs in Europe and India, but is not yet definitely 

 known to occur in Africa), the labella, though somewhat larger, are 

 similarly chitinised and armed, and they and the rest of the proboscis 

 doubtless act as in Stomoxys, though it is possible that the proboscis 

 does not penetrate so deeply into the skin of the victim. In 

 Philcematomyia, however, in which the labella are large and fleshy, 

 as in Musca, though, as has been seen, the proboscis is also provided 

 with powerful teeth, there is strictly speaking no actual piercing 

 organ, since the fleshy termination of the proboscis would seem to 

 be incapable of being thrust into the skin of a Vertebrate. The 

 fly therefore in all probability feeds by cutting through the epidermis 

 with the teeth at the end of the tubular extension, and then sucking 

 up the blood in the ordinary way. 



Specimens of Philcematomyia insignis, Austen, were taken at St. 

 Louis, Senegal, on May 16th, 1903, " feeding on cattle and donkeys," 

 by the late Dr. H. E. Dutton and Dr. J. L. Todd, and at Zambie, 

 R. Congo, Congo Free State, in September, 1903 (Drs. Dutton, 

 Todd, and Christy) ; additional examples have also been received 

 from Cyprus, Sokotra, India, and Ceylon. In Cyprus, according 

 to information received from Dr. G. A. Williamson, Ph. insignis 

 attacks human beings and horses, and the latter become very 

 restive when bitten. 



The African blood-sucking Muscidse (exclusive of Glossina) at 

 present known vary in length from about 2.5 mm., in the case of 

 a small specimen of Lyperosia thirouxi, Roubaud, to 7 mm. in that of 

 Stygeromyia sanguinaria, Austen, or a large species of Stomoxys, 

 such as S. inornata, Griinberg. The coloration of the body is dull 

 (some shade of grey, brown, or blackish, with darker markings), 

 while the wings, which in the resting position lie in the horizontal 

 plane, diverge more or less at the tips, and may, as in Lyperosia, 

 overlap to some extent at the base, are hyaline or infuscated, 

 but never mottled. The horizontal, chitinous, proboscis is visible 

 from above in the case of Stomoxys, but in Lyperosia, in the normal 

 resting position, is concealed by the palpi ; in Stygeromyia, owing to 



