126 



Sevvell (E.). a Note on the Importance of the Genus Hahronema 

 as an Economic Factor amongst the Equidae oJ the Punjab and 

 the North-West Frontier Province. — Agric. Jl. India, Calcutta, 

 xvi, pt. 2, March 1921, pp. 152-155. 



In the stomachs of horses and mules destroyed for chronic debihty 

 in the Punjab and the North-West Frontier of India serious lesions 

 due to one or more species of Hahronema were found in every case. 



The life-histories of H. megastoma, H. iniiscae and H. microstoma, 

 and remedial measures and treatment for them are quoted [R.A.E., 



B, vi, 13, 202; vii, 118, 157; viii, 51]. 



Oil of chenopodium is recommended as a vermifuge. It can be 

 used alone, or with chloroform followed by linseed oil and turpentine. 



Root (F. M.). Experiments on the Carriage of Intestinal Protozoa 

 oJManbyFlies.— .4wtT. //. Hyg., i, no. 2, March 1921, pp. 131-153, 

 3 plates, 8 tables. 



Flies have been proved to carry cysts of intestinal protozoa, including 

 Entamoeba histolytica which causes amoebic dysentery [R.A.E., B, 

 v, 117, 151], and the author describes experiments to prove whether 

 these cysts pass through the flies entirely unaltered or are killed by 

 too long a sojourn in the fly's alimentary tract. 



It was found that free forms of E. histolytica and Chiloniastix 

 mesnili swallowed by flies die within an hour, never encysting. 

 Motile C. mesnili have appeared in the fly's faeces 7 minutes after 

 feeding on a stool containing them. 



The survival of cysts of intestinal protozoa in the fly's intestine 

 varies according to the species. Half the cysts of E. liistolytica were 

 dead after 15 hours, the last living surviving 49 hours. Half the cysts 

 of E. coli were dead after 14 hours, the last living surviving 52 hours. 

 Half the cysts of Endolimax nana were dead after 18 hours, the last 

 living surviving 39 hours. Half the cysts of Giardia intestinalis were 

 dead after 8 hours, the last living surviving 16 hours. Half the cysts 

 of C. mesnili were dead after 36 hours, the last living surviving 80 

 hours. Cysts in drowned flies survive much longer. Half the cysts 

 of G. intestinalis were dead after 2 days, the last living surviving 

 4 days, and those of Entamoeba histolytica survived 7 days, half of 

 them dying in 3 days. 



The amount a fly can eat depends on the period of starvation. 

 Experiments pro\^e that a common house-fly {Mitsca domestica) 

 can digest 0-0068 cc. of fluid, and a single blow-fly {Calliphora 

 erythrocephala) 0-022 cc. 



An infection with Herpetomonas miiscae-domesticae was only found 

 in one of 225 specimens of Miisca domestica examined at Baltimore. 

 Two infections with H. calliphorae were found in 124 specimens of 



C. erythrocephala. 



The relation of flies to the spread of intestinal protozoan infections 

 appears to be that fly faeces are only dangerous to human beings if 

 deposited on moist or liquid foods. Flies may deposit infective forms 

 from a few minutes after feeding until the cysts are dead. The earlier 

 hours are the most dangerous as the larger proportion of cysts are 

 then alive. It is possible that human beings may be infected b}^ 

 swallowing liquid in which flies have been drowned, as cysts live 

 about a week in these cases. 



