ENTOMOLOGICAL SOCIETY OF ONTARIO. 97 



has been used with success by Prof, Gillette on cattle and hogs and by Dr. Orcutt and 

 Mr. Alkrich for sheep dip, but Prof. Francis pronounces it less satisfactory than some of 

 the proprietary combinations for ticks on cattle. I have also seen some reports of poor 

 success with it or apparent injury, especially to lambs, from its use. 



While I fully believe in its efficiency when properly made and applied and would 

 attribute failures to improper preparation, the fact that such failures occur in practice is 

 somewhat unfavorable to the general adoption of this remedy. 



The various powders used are tobacco, sulphur, pyrethrum, snuff, and common road 

 dust (the latter presumedly acting by closure of the spiracles) and of the other substances, 

 tobacco or preparations including this material may probably be considered as most 

 generally useful, 



Pyrethrum if dusted in among the hairs so as to thoroughly reach the insects when 

 first applied, is quite effective and may be used for fleas and lice, but probably would not 

 affects the mites. 



Fumigation is a method which presents some advantages where it is practicable, be- 

 cause it can be used during winter when washes are objectionable and is preferable to 

 powders, because all of the individuals affecting an animal may be killed and thus en- 

 tirely free it, whereas by the other method the survival of a few individuals may restock 

 the animal. A simple plan of adopting this is to cover the animal^with a blanket, leaving 

 the eyes and nose exposed, but having the blanket reach the floor or ground and made as 

 tight as possible at all points to prevent the escape of fumes. Puff" tobacco smoke under 

 this blanket by means of a bee-smoker. This plan first came to my notice as recom- 

 mended by Mr. Charles Aldrich, who claims for it very effective work. I have also seen 

 a description of a plan for fumigation of fowls which involves the same principles. Some 

 years ago I suggested the plan of using a tight stall, with an opening at the head, a can- 

 vas protection, so as to leave the head, eyes, and nose exposed and free ; and some 

 experiments with this method showed that fumes of either sulphur or tobacco are verv 

 effective in destroying lice, both the Pediculidaj and Mallophagidaj. The time of exposure 

 to the fumes varied from twenty to twenty-five minutes in these experiments. The sul- 

 phur or tobacco were burned over an alcohol flame, but I should presume a preferable 

 plan would be to place the substance in a tin or sheet-iron tube, closed at one end with 

 the open end projecting into the stall, and drive the fumes off" by means of heat applied 

 to the under surface. The common little lamp-stove could be used. The stall should be 

 made as small as possible to accommodate the animal, in order that the fumes may be as 

 dense as possible, and on this account the simple covering with a blanket is perhaps pre 

 ferable, as it adjusts itself to the animal, but provision should be made for the free 

 circulation of fumes on the parts of the animal where the blanket would press. 



I^eding of sulphur with salt is strongly recommended by some, and Mr. Weed, of 

 Mississippi Station, gives it a strong endorsement as a result of experiments at that 

 station directed especially against the cattle tick {Ixodes hovis, Riley). 



Mr. Gillette asked how the hen louse could be destroyed. 



Mr. Osborn, in reply, said he thought the use of tar on the ends of the poles in the 

 henhouse could be made to answer the purpose. 



Mr. Aldrich thought it not safe to recommend kerosene for destroying insects on 

 animals, because of the injurious effect on the skins of the host. 



Mr. Gillette replied that he agreed that kerosene should not be used for sheep, but 

 for hogs and cattle it was useful. 



Mr. Riley remarked that he was deeply interested in a change of opinion resulting 

 from later experience and experiments regarding the usefulness of the kerosene emulsion 

 in destroying animal parasites, and particularly in Mr. Gillette's altered experience in re- 

 ference to its use on sheep. He thought, however, that the difficulties of making a good 

 kerosene emulsion and of getting intelligent farmers to use it safely were unnecessarily 

 magnified. He could not accept the doctrine that of two given remedies the poorer one 

 was to be recommended because the better required a little more care and intelligence in 

 making and using. 



Mr. Hopkins had used sulphur for stock at all times and found it not injurious 

 7 (EN.) 



