990 EXPERIMENT STATION RECORD. 



not SO easily destroyed ;;s those upon sniootli surfaces. For purposes 

 of studv the Itest material on which to dry spores is pure quartz sand. 



Notes on roup, H. ^V. ^Iaksiiall {Rhode IxlancI Sta. Rj>t. 1.900, 

 pj>. 2-jo-JJ4.Jf). — Fi'om diseased chickens 6 forms of bacteria were 

 isolated in pure culture, and an experiment was conducted in attempt- 

 ing to inoculate other chickens by means of these cultures. During 

 this experiment 12 hens were arranged in 6 pairs, and each pair received 

 dailv in drinking water a portion of one of the pure cultures. After 

 6 weeks of this treatment all the chickens remained healthy. The 

 chickens from which the original roup material was taken were 

 ati'ected in the nostrils and eyes, but did not show any diphtheritic 

 membrane in the throat. Both of these chickens subsequently died. 

 Since it was suspected that the roup organism might develop more 

 vigorously on a medium prepared out of chicken meat, the author used 

 a medium known as rooster agar. 



In order to determine the extent of natural transmission of roup, 

 pullets and 4 hens were confined with a roupy hen. and the eves of the 

 healthy fowls were rul)l)ed daily with the exudate from the sick bird. 

 All fowls were permitted to drink from the same receptacle. During 

 2 months 2 of the pullets died and 2 others showed slight swellings 

 about the eyes. None of the 4 more vigorous ones ])ecame sick. The 

 author made a microscopic examination of roup tissue taken from the 

 ej^es and throat of diseased fowls. Besides various bacteria found in 

 this material, a smaller number of rounded, deeply stained bodies 

 were distinguished, and it is suggested that these may prove to be some 

 form of protozoa. An attempt was made to secure pure cultures of 

 this round organism without success. 



In order to obtain experimental evidence on the question of the 

 identity of the roup organism with the diphtheria bacillus, a number of 

 fow^ls were confined and fed daily with bouillon cultures of Baeillvs 

 diphtJier'Ki. After 6 weeks the fowls were killed and found to ])e free 

 from diphtheria. Later -i hens were inoculated sul)cutaneously with 

 virulent cultures of the diphtheria bacillus, but no case of diphtheria 

 was developed in the hens. 



The susceptibility of certain species of animals to the organism 

 of hemorrhagic septicaemia of ducks and chickens, A. Kabikaux 

 ( ( ninpf. R< ltd. S,h: B!,J. Puri^. ■'>2 {1000), No. 7. pp. 166-1.58).— In ducks 

 and chickens the disease is easily produced by ingestion of cultures 

 or food su})stances in which the organism is mixed. Death takes 

 place within from 30 to 48 hours without symptoms except diarrhea 

 near the end of the period. In the pigeon death results within 

 al)out the same length of time after eating cultures of this oro-anism. 

 The ra]>bit is very susceptible, and contracts the disease either by 

 ingestion of the organism or by inhalation. In the latter casc^ ])ulmo- 

 nary lesions appear. 



