578 EXPERIMENT STATION RECOED. 



Souma, the trypanosomiasis of French Soudan, G. Bouffakd {Ann. Inst. 

 Pasteur, 21 {1901), Wo. 7, pp. 587-592). — The author had opportunity to study 

 souma in zebus, horses, asses, and mules. The disease occurs in acute and 

 subacute forms. The blood parasite is sometimes found in the periphei'al blood 

 but is comparatively rare and nonmotile. Souma also occurs in sheep. The 

 period of incubation is about 7 days. The pathogenic organism is Trypanosoma 

 cazalboui, and is probably carried by Glossiua palpaJis. Benzidin causes the 

 disappearance of the trypauosomes from the blood but does not bring about 

 complete recovery. 



Role of the spleen in trypanosomiases, A. Laveban and A. Thieoux {Ann. 

 Inst. Pasteur, 21 {1907), No. 8, pp. 593-612). — Experiments were made on 

 guinea pigs and dogs with Trypanosoma evansi, T. pecaudi, and other species. 



It was found that trypanosomes taken from the spleen during life or im- 

 mediately after death were not to be distinguished from those in the general 

 circulation. The extract of the spleen showed no trypanolytic action in vitro. 

 The development of trypanosomes pursued a perfectly normal course in ani- 

 mals from wliicb the spleen had been removed. It is believed, however, that 

 the spleen assists in removing from the blood the remains of blood parasites 

 during the progress of trypanosomiasis. 



Some forms of spirochetosis met with in animals in India, A. Lingard 

 {Jour. Trop. Vet. Sci., 2 {1907), No. 3, pp. 261-286, pis. 3).— An intense interest 

 has lately developed in the study of Spirochseta. Careful distinction is made 

 between Spirillum and Spirochfeta, and in the author's opinion the family 

 TrypanosomidJB includes the genera Spirochseta, Treponema, Trypanosoma, 

 and Trypanoplasma. The literature relating to Spirochseta in animals and man 

 is reviewed. Particular attention is given to the occurrence of these organisms 

 as observed in India in Indian cattle, camels, horses, and elephants. 



Hemorrhagic septicemia of cattle, and its relation to preventive vaccina- 

 tion, F. S. H. Baldrey {Jour. Trop. Vet. Sci., 2 {1907), No. 3, pp. 287-309, pis. 

 6). — This disease is considered identical with barbone, pasteurellosis of cattle, 

 etc., and has a wide distribution. The symptoms and lesions of the disease are 

 described in detail. Hemorrhagic septicemia causes death by the rapid elimi- 

 nation of the toxin. The virulence of the organism is long retained in dust but 

 is quickly lost in ordinary cultures, especially if exposed to light. The virulence 

 is apparently diminished by passage through rabbits. 



So long as the intestinal mucous membrane is intact, infection probably does 

 not take place by feeding. Protective vaccination is possible by means of sub- 

 cutaneous injection of the dead mici'o-organisms, but protective serum seems to 

 exert little effect. 



Texas or ticlt fever, C. A. Gary {Alabama Col. Sta. Bui. llfl, pp. 109-186, 

 figs. 9). — The history, etiology, and distribution of Texas fever are briefly dis- 

 cussed. When the number of red corpuscles affected by the blood parasite 

 exceeds -1 per cent fatal results usually follow. It lias been estimated that 

 300,000 ticks, a not impossible infestation of a single animal, would withdraw 

 200 lbs. of blood from the host. 



An account is given of the life history of the tick, the symptoms, diagnosis, 

 and pathology of Texas fever, and methods of producing immunity. Immunity 

 to this disease, however, is merely relative. At the experiment station, 493 

 cattle have been inoculated with the result that the total percentage of deaths 

 within 1 year after inoculation was 14.8. 



Descriptions are given of the cattle tick and other related species. In Ala- 

 bama the period of egg laying varied from 17 to 40 days, while the average 

 length of life of ticks in summer and autumn was 22 days and of the larvae in 



