276 [December, 



R.N., noticed the same peculiar liabits of these small Diptera when 

 collecting at Yala (S. E. Ceylon), as the following extract from his 

 journal will show : — 

 T. Bainbrigge Fletcher, at Yala (S. E. Ceylon), February 9th, 1909. 

 " Wheeling about swiftly but heavily in the bright sunshine 

 was a large black Coprid beetle, which seems very like the figures 

 of Ateuchus sacer, but larger.* I saw no individuals except on the 

 wing, so cannot say whether they were in search of any particular 

 kind of dung. At the time, however, they seemed to be attracted 

 in some degree by fresh buifalo's dung as I saw several flying about 

 in its vicinity. I seem to remember, however, reading in Tennent's 

 book of a large Coprid Ijeetle peculiar to the elephant, and it may 

 perhaps have been this animal's dung of which they were in search. 



" The most interesting point, however, about these beetles was the 

 fact that they were all carrying about small winged Diptera, which 

 ran actively about over the ventral surface of the thorax and abdomen 

 of the beetle, reminding one in their movements of the flies parasitic 

 on bats, but seemed loathe to use their wings, even when the beetle 

 had been caught and was being handled. Of four beetles caught, one 

 was carrying 12 of these flies, another 3, and the other two, 3 between 

 them ; but it is very probable that in the last three cases some of the 

 flies had been brushed ofl: in netting the beetle or during its struggles 

 in the net. 



" Green found these flies at Trineomali on a Coprid beetle which he 

 showed me at the time, and afterwards recorded in ' Spolia Zeylanica ' 

 (vol. iv, p. 183). He speaks, however, of the beetle as their 'host,' 

 thereby inferring that the flies derive their nourishment directly from 

 the beetle : but, unless the mouth parts of these flies support the 

 assumption that they are able to penetrate between the tough ventral 

 plates of the beetle, I am inclined to look upon these flies as filling 

 the role rather of passengers than of parasites in the strict sense of 

 the word. It seems to me probable that these flies feed during their 

 early stages, and perhaps during the adult stage also, on the same 

 sort of dung which forms the food of the beetle, and that they cling 

 to the beetle only as a means of easy transport to, and discovery of, 

 their pabulum. As against this t view, however, it should be added 

 that I noticed the abdomina of some of these flies to be very swollen, 

 as is the case in the ? Hippobosca when its embryo is ready for 

 expulsion, so perhaps the flies may be pupiparous. In this case, the 



* Later Note — Determined by Mr. Arrow as Scarabceut gangeticus. 

 t "this view," t.<., that the larva; of the flies are dung-feeders. 



