382 EXPERIMENT STATION EECORD. 



infected with TryiHiHosottia evansi, the causative agent of surra. The 3 in- 

 fected animals were destroyed July 20 and the remaining cattle protected 

 from blood-sucking Hies and mosquitoes which swarmed around the corral in 

 countless numbers, " On completion of the screening of the south and east sides 

 of the corral an abundant supply of sticky and i)oisonous fly paiier was spread 

 about within the inclosure, and very shortly all the Tabanus atratus were 

 caught or destroyed, along with large numbers of the other Tabanidte and 

 Stomoxys calcitrans, one of the Muscidie. However, a considerable number of 

 the latter siiecies and a few T. lineola and T. costalis still remained, and it 

 seemed impossible to eliminate them by this temporary screening." 



In a .second series of inoculations made July 31, 7 animals were found in- 

 fected and were destroyed. A specially constructed fly-proof stable containing 

 individual fly-proof box stalls was then erected for the purpose of eliminating 

 all kinds of flies, and especially the stable fly, S. calcitrans, considered by some 

 authorities as being capable of transmitting trypanosomal infections. " After 

 this second test it seemed plausible to consider that only the Tabanidte — and 

 probably only the 'Tabanus atratus — were responsible for the spread of the in- 

 fection, and that the disease would be eradicated with the elimination of those 

 animals which had been infected by these flies previous to July 27, when this 

 Tabanus was eft'ectually excluded as a factor in the conveyance of the in- 

 fection." 



Four additional animals were found infected on August G and 4 on August 

 11 and were destroyed, making a total of 18, Further injections of blood 

 resulted negatively and the remaining animals, 33 in number, were released 

 from quarantine on November 4, IDftO. 



The investigations led the authors to conclude that there were only 3 in- 

 fected zebus at the time of arrival of the cattle in quarantine and that the 

 others became subsequently infected by means of the plague of flies present in 

 the vicinity of the quarantine station. 



The authors discuss the history of the importation of Indian cattle into 

 America, the characteristics of Indian cattle, the nature of the causative agent 

 of surra and the disease which it produces, rabbit experiments with infected 

 blood, and the role of the TabanidiB in the transmission of surra. 



" It has been definitely shown that in surra as well as in other trypano- 

 somal infections microscopical examination of either stained or unstained 

 blood films will not suffice in making a diagnosis, and that the only satisfactory 

 results are obtained by animal, particularly rabbit, inoculations. 



" Relative to further importations into the United States of any class of sus- 

 ceptible animals from surra-infected countries for agricultural purposes or 

 for menageries or zoological gardens, the experience gained in this outbreak 

 indicates that it would be imprudent to import such possibly infected animals 

 without testing each individual, either before or after arrival, by blood inocu- 

 lations of susceptible small animals, ])referably rabbits." 



The susceptibility of the dog' to African horse- sickness, A. Theileb 

 (Jour. Compar. Path, and Tlicr., 23 {1910), No. 4, pp. 315-325).— This reply 

 to the account previously noted (B. S. R., 23, p. 391) includes a report of 

 further experiments, 



" Of 2 dogs injected subcutaneously with 5 cc. of a filtrate mixture obtained 

 by diluting 1 cc. of virus with 4 cc. water and passing the mixture through a 

 Berkefeld filter both contracted typical horse-sickness reactions, and one died 

 with all the lesions of horse-sickness on post-mortem examination. The blood 

 of the dog which died, tapped during the reaction and 2 cc. injected subcu- 

 taneously into a mule, communicated typical horse-sickness of an acute type. 



