- 3 - 



5-Methyl-5-nitro-2-propyl-m-dioxane (0-7102) was more effective than 

 1;1' -oxybis^-hexyloxyJ-S-propanol (0-^200), but the latter compoiAnd 

 appeared to be moire effective sigainst Tabsjius sonomensis 0. S. and 

 productus Hine, giving fairly consistent protection for 1 or 2 days. M-250 

 was the least effective material tested in the field, giving protection for 

 2 to 5 hours. 



The pyrethrum sprays- gave poor protection unless used at very high 

 concentrations. The pyi^thrins at 0.1 to 0-3 percent ccJncentration plus 

 p-aminophenol or triple -distilled teLLl oil applied at the rate of 1 quart 

 per animal gave l/2 to 2-l/2 days ' protection as emulsion sprays . Piperonyl 

 butoxide in combination with the pyrethrins was somewhat more effective. 



In general, the repellency of the various materials was similar to 

 that in the laboratory tests. However, all except the pyrethrins had some 

 deleterious effect on the skin and hair of the animal. 



Summary 



A total of 258 synthetic organic compounds were tested in the 

 laboratory as repe3J.ents of the deer fly ( Chrysops discalis Will.) with 

 white mice as the host animals . Only a few of the compounds showed any 

 promise as long-lasting repellents, 2-amino-3-isobomyloxy-2-methyl-l- 

 propanol (0-4265) and Santomerse DT (0-16^+84-) being the most effective. 



Five of the best materials were tested on calves in the field 

 against mixed populations of tabanids . The most effective were 2-ainino- 

 3-isobomyloxy-2-methyl-l-propanol ajid Santomerse XXT. All the materials 

 tested except the pyrethrins were slightly deleterious to the hair and 

 skin of the animals. The protection obtained ranged from about 2 hours 

 to 3-I/2 days. Pyrethrum sprays were not very effective unless used at 

 very high concentrations. 



Literatxire Cited 



Eddy, Gaines W. , and W. S. McGregor. 19^9. Use of white mice for 

 testing materials used as repellents and toxicants for stable 

 flies. Jour. Econ. Ent. k2{3): k6l-k63. 



