590 SUMMARY OF CUERENT RESEARCHES RELATING TO 



maltose, or saccharose. It does not produce indol, and does not blacken 

 lead agar ("gelose an plomb"). It has a tendency towards autolysis. 

 Practically, the bacillus may be considered as avirulent, but it has strong 

 toxin-producing powers. The toxin produces characteristic symptoms 

 and lesions among rabbits (emaciation, paralysis of the fore-quarters, 

 diarrhoea, and coma). The toxin resists the action of heat and acids. 



Etiology of Infectious Anaemia of Horses.* — Caire and Vallee 

 summarize the results of their protracted investigations into the etiology 

 of equine infectious ana?mia as follows : — The malady is infectious, 

 inoculable, and due to an ultra-microscopic filter-passer. The blood and 

 urine of the sick horses are infective. The virus is destroyed by heating 

 to 60° C. The infection is present in the digestive tract and in the 

 urine. Horses to all appearances healthy may in reality be infective, 

 and may spread the disease to other animals. 



"Kie illness is transmitted by the digestive passages. In the course 

 of its evolution the anjemia presents violent paroxysms, characterized 

 by fever, haBmatogenous jaundice, and hjemaglobinurea. The blood has 

 a low hajmaglobin index, and is of low coagulability. The red cells 

 agglutinate, and the serum is strongly stained and dichroic. In the 

 intervals between the crises, the disease is manifested by albuminuria 

 and by the condition of the heart. Post-mortem splenomegaby, a large 

 " cardiac " liver, endocarditis, and changes in the marrow of the long 

 bone are manifested. Separation, surveillance of sick animals, disinfec- 

 tion of dejecta, and protection of drinking-water, are strongly indicated 

 in prophylaxis. The destruction of the bodies of the sick animals is also 

 indicated. Up to the present, vaccination and serum-therapy have been 

 barren of results. 



Destruction of Schistocerca peregrina in Morocco. f — H. Vein and 

 A. Bouin have carried out a series of painstaking investigations in 

 Morocco with d'Herelle's Coccobacilhis acridiorum, and find that the 

 exaltation of the bacillus to the point of killing the insect in three 

 or four hours by means of intra-abdominal inoculation is comparatively 

 easy. The virulence of the organisms, however, varies with the tempera- 

 ture, the age of the locusts inoculated, and the age of the cultures. A 

 virus, for instance, which kills in three to four hours at 25'-/)0° C. 

 takes eight to ten hours to kill at 15°-20° C. ; and a virus which kills 

 a locust fifteen to twenty dayB old in four hours may take as long as 

 fourteen hours to cause the death of a thirty to forty days' old insect. 



The methods of d'Herelle gives encouraging results, but it is difficult 

 to appraise their exact value. The virulence of the cultures is very 

 fugative, and as the epidemic spends itself the proportion of the 

 morbidity to the mortality gradually increases. The evolution of the 

 epizootic is conditioned by the number of diseased locusts which fall 

 victims to their healthy comrades, and the infection may be artificially 



* Ann. Inst. Pasteur, xxx. (1916) pp. 383-8. 

 t Ann. Inst. Pasteur, xxx. (1916) pp. 389-421, 



