360 MEDICAL BACTERIOLOGY 



h. Ordinarily the organisms are very sparse and large quantities 

 must be used. 100-1000 cc. are placed in flasks and 1% of peptone 

 and 0.5% salt are added, the fluid made alkaline and incubated at 

 38° C. for 6-24 hours. Then gelatin plate cultures are made from 

 the upper layers and the suspicious colonies worked up as above. 



Here and in typhoid the agglutination of the germ with great 

 dilution of a high potency serum is the crucial test. 



Bacterium anthracis (Eobert's Method.) 



a. Heat suspected water to 80° for ten minutes to kill water 

 bacteria. 



b. Make plates in agar and in gelatin and work up colonies. 



c. Inoculate a guinea pig with several cubic centimeters of the 

 water. 



Eefeeences. Horrocks and Prescott & Winslow. 



EXERCISE 109. EXAMINATION OF MILK FOE PATHOGENIC 

 BACTEEIA. 



Bacterium diphtheriae. 



Where Bacterium diphtheriae is suspected in milk, make a con- 

 siderable number of streak cultures on LoefSer's blood serum and 

 incubate at 38° C. from 8 to 12 hours, stain and examine micro- 

 scopically. 



Bacterium tuherctdosis. * 



Hammond's method of examining milk for B. tuberculosis. See 

 Sputum, 101. 



Animal Inoculation. 



USE OF MAIL FOR TRANSMISSION OF BACTERIA. 



Concerning the transmission of material containing bacteria in mails, see 

 Postal Guide, 1898, Ruling No. 82, p. 901, part of which is as follows: "That 

 the order of the Postmaster-General of June, 1893, forbidding the use of 

 m"_ils for the transmission of specimens of germs of cholera or other diseased 

 tissues, is hereby modifieci to this extent: Specimens of diseased tissue may 

 be admitted to the mails for transmission to United States, State or munic- 

 ipal laboratories only when inclosed in mailing packages constructed in 

 accordance with the specifications hereinafter enumerated. Upon the outside 

 of every package shall be written or printed the words: 'Specimen for Bac- 

 teriological examination.' No package containing diseased tissue shall be 

 delivered to any representative until a permit shall have first been issued by 

 the Postmaster-General, certifying that said institution has been found to 

 be entitled, in accordance with the requirements of this regulation, to receive 

 such specimens." 



