148 



Among tlie remedial measures proposed by Dr. Portchinsky ia 

 tlie siig-gestion that horse dung', before being stacked in heaps for 

 manuring purposes, should be spread in thin layers in the sun or 

 wind, so as to dry it ; this will free the dung from the larvae of 

 S. calcitrans and 21. domestica. Or again, the dung may be 

 moistened with kerosene or naphtha waste, which will not destroy 

 its fertilising qualities, but will only delay its decomposition. 

 Stables should be sprayed with the same substances two or three 

 times a week. Experiments are described showing that kerosene 

 quickly kills the larvae of both these flies ; chloride of lime is 

 also very effective. The burning, or at least the thorough drying, 

 of all waste products of agriculture, before stacking as manure, 

 is also stronglv recommended. 



Serkes (J.). Estridia de los ovinos [Oestrus ovis]. — Gaceta Rural, 

 Buenos Aires, vi, April 1913, pp. 759-761. 



This fly was first recognised in Argentina by E. Wernicke in 

 1888, and again by H. Eivas in 1889; since that time it has been 

 constantly found and is now a well known pest. The life-history 

 of the fly is described and the author says that the adults lodge 

 in cracks and holes in the walls of sheepfolds, from which they 

 emerge when the weather is hot and dry. The sheep endeavour 

 to avoid them by flinging themselves on the ground and trying- 

 to bury their noses in the earth, or by gathering together in 

 groups with their heads towards the centre. Sometimes it would 

 appear that the sheep purposely raise clouds of dust by stampings 

 on the earth to drive away the common enemy. 



The symptoms and course of the disease are described in 

 detail. Spontaneous cures occur occasionally, in consequence of 

 the inflammation set up facilitating the expulsion of the larvae 

 by violent sneezing. 



The disease is exceedingly difficult of treatment ; medication 

 through the nasal fossae is useless and does not kill the larvae, 

 but only worries them and causes them to change their position : 

 further, their resistance to drugs, of any kind which it is possible 

 to use, is very great. The author says that the only way of 

 attacking them directly is to trepan the skull above the nasal 

 fossae and remove the larvae, but this is impossible without the 

 intervention of a skilled veterinary surgeon ; and the best plan 

 is to send infected animals to the slaughter house. 



He considers that the flght against the adult fly is practically 

 without result and is not worth attempting, but that something 

 may be done by the patient destruction of all larvae which the 

 sheep expel from their nostrils and also of all those found in the 

 heads of slaughtered animals. The sheepfolds should be 

 thoroughly lime-washed from time to time and all holes and 

 cracks which might serve as lodgment for the flies should be 

 carefully stopped up. Rivas has suggested painting the end of 

 the nose of the sheep for two or three days with tar or with crude 

 empvreumatic wood oil, which he savs will prevent the attack 

 of the fly. 



