90 EXPERIMENT STATKJN RECORD. 



"without iivatiuL-nt of tlif abraded !^nrt'ace8 with (•t)rroHivt' (jul)limate. The 3 con- 

 trol animals developed rallies after 174, J 77, and 2H9 days, respectively, and all died, 

 the course of the disease occupying 12, 40, and 24 days, respectively. None of the 

 other 10 animals developed symptoms of rabies durinjj: the period of (jbservation, 

 which amounted to 582 days. The author believes that these experiments indicate 

 the possibility of a longer incubation period for rabies than has usually been 

 estimated. 



Behavior of rabies virus in the central nervous system of susceptible, nat- 

 urally immune, and immunized animals, R. Krais et al. {Ztiirhr. Ilijg. a. Ivfec- 

 tiouxkmnk., 41 {1902), No. S, pp. 4S6-o£6). — The extensive experiments of these 

 authors were undertaken for the purpose of obtaining information on the question 

 whether raljies virus is propagated throughout the organism by way of the nervous 

 system. The experiments were made on rabbits, pigeons, and hens. It M'as found 

 that the different portions of the centi-al nervous system, after a subdural infection 

 with the virus of rabies, Ijecome infectious at different periods of time. The medulla 

 was found to be infectious after 3 or 4 days when injection was made with laboratory 

 virus, while from 6 to 10 days were required for the same process to take place after 

 injection with virus from rabid animals just dead of the disease. The differences in 

 the rapidity with wliich the 2 kinds of virus propagate themselves along the central 

 nervous system is believed to be due to the difference in the active powers of multi- 

 plication of the different viruses in the nervous tissue. Further experiments of the 

 authors indicate that the virus is not propagated in the dead brain of susceptible 

 animals, but only in the brain of living animals. The authors believe that they 

 have demonstrated that rabies virus is capable of projjagating itself and that the 

 negative results from transmission experiments with rabbits are due to the attenua- 

 tion of the virus. Experiments with immunized rabbits showed that these animals 

 are capable of resisting infection and that the virus of rabies is destroyed in the cen- 

 tral nervous system.. Immunity toward the disease is therefore believed to reside 

 in the central nervous system, but the actual mechanism of this immunity is not 

 understood. 



The formation of substances immune toward rabies virus in naturally 

 susceptible and insusceptible animals, R. Kraus and R. Maresch (Zt.^ehr. Ilyg. 

 n. Infedioih^kraiil:,41 [1902), No. 3, pp. 527-539). — The results of the authors' exper- 

 iments may be briefly summarized as follows: Suscei)tible rabbits and dogs do not 

 normally possess any sulistance antagonistic to rabies in their serum. Such sub- 

 stances are developed, however, in these animals after immunization with laboratory 

 virus. In susceptible pigeons, only those which have been treated with laboratory 

 virus develop any immune substance in the blood. Chickens, which are only 

 slightly susceptible to rabies, normally have substances antagonistic to rabies in the 

 serum, but do not produce any more of these antagonistic bodies after immunization 

 with laboratory virus. 



A bacillus found in animals and resembling that of influenza, A. Wolff 

 [Centhl. Bald. ii. Par., 1 Ahi., S3 {1903), Nn. G. Oritj., jyp. 407-411, til/, i).— In experi- 

 ments undertaken for the purpose of securing a cholera toxin the author discovered 

 an organism in rats which proved to be slightly pathogenic for these animals. The 

 organism closely resembles the bacillus of influenza, and descriptive notes are given 

 on its morphdlogy and biology. The organism is only slightly pathogenic for rats, 

 guinea pigs, and other experimental animals, as shown by inoculation experiments. 



A new bacillus belonging to the influenza group, E. Freidberger {Centhl. 

 Bakt. u. Par., 1. Ahi., 33 {1903), No. 6, Orig., pp. 401-406, jigs. 2).— The. author 

 isolated from dogs an organism which he names Bacillus h;niioglohinophilus caiiis and 

 which showed a striking resemblance to the bacillus of influenza. Notes are given 

 on th-' behavior of this organism on various culture media. It proved to be slightly 

 pathogenic for guinea pigs and other experimental animals. 



