412 Journal of Agricultural Research voi. xii. no. 7 



carbons of petroleum and is probably more like the commercial gasoline 

 used by Stiles {1901) than the present-day commercial product.^ 



Two full-grown sheep were used for the experiment. The animals were 

 starved for 24 hours and then given 15 mils of petroleum benzin in 150 

 mils of milk, on three consecutive days. They were drenched through a 

 tube held in the mouth. In no case were any symptons of intoxication 

 from the fumes of the benzin observed during or after its administration, 

 and the post-mortem showed no lesions which could be attributed to the 

 action of the drug. 



The chief points of interest in this experiment are : 



(i) The apparent superiority of refined gasoline (petroleum benzin) 

 over commercial gasoline as an anthelmintic for stomach worms {Hae- 

 monchus contortus) and hookworms {Bunostomum trigonocephalum). 

 It proved 88 per cent efficacious for stomach worms while the latter was 

 only 35 per cent efficacious, as shown by the summary of three experi- 

 ments. Its efficacy against hookworms is still more marked. It was 

 73 per cent efficacious for this parasite, while gasoline proved only 5 per 

 cent efficacious. 



(2) Its entire inefficacy against nodular worms (Oesophagostomum 

 columhianum) . No worms of this species were removed by petroleum 

 benzin, while the three experiments with gasoline showed an efficacy of 

 16 per cent for this parasite. 



The post-mortem examination of the two sheep showed that they were 

 both very lightly infested with stomach worms {Haemonchus contortus), 

 most of which had been removed by the treatment. The remedy re- 

 moved all hookworms (Bunostomum trigonocephalum) from one sheep 

 and more than half the number present from the second sheep. It was 

 entirely inefficacious against other intestinal nematodes and tapeworms 

 (Moniezia spp.). Its failure to destroy any of the nodular worms 

 (Oesophagostomum columhianum) in the large intestine may be explained 

 on the grounds that it is perhaps more readily absorbed than commercial 

 gasoline, and, hence, was largely absorbed before reaching the colon. 

 It should be pointed out that in this experiment the animals were starved 

 for 24 hours before treatment, while in the experiments with gasoline they 

 were not starved. This may have had something to do with the results 

 notwithstanding the slowness with which the rumen becomes empty when 

 sheep are starved. 



In summary it may be stated that petroleum benzin showed marked 

 superiority over commercial gasoline as an anthelmintic both for stomach 

 worms (H. contortus) and hookworms (B. trigonocephalum). While it 

 did not quite equal the treatment with the copper-sulphate drench as a 



1 According to the issue of the Journal of the American Medical Association for October 14, 1916, the 

 present commercial gasolineincludeshydrocarbonsdistillingatatemperatureashiKh as 175° C. (Tydeman, 

 F. W. I,. NAPHTHALENE IN GASOLINE FOR AUTOMOBILES. In Jour. Amer. Med. Assoc, v. 67, no. 16, 

 p. II75-) 



