WHOOPING-COUGH. 599 



hour or so it separates into a fluid portion and a mass of 

 whitish, opalescent, irregularly formed flakes or frag- 

 ments. These were selected for study, and were trans- 

 planted by means of a platinum-wire hook to the cul- 

 ture-media. Czaplewski and Hensel used a rather better 

 technique than this, and secured purity of the bacteria 

 in the flakes by transferring them to a test-tube contain- 

 ing pepton solution and violently agitating the tube to 

 wash off foreign bacteria. After washing, the flakes were 

 sown upon culture-media. 



Hydrocele-fluid was found most useful as a culture- 

 fluid, but particles of sputum were planted upon all 

 the culture-media, and attempts to cultivate bacteria from 

 them were conducted both aerobically and anaerobically. 

 In 13 out of the 16 cases the same bacillus (x) was iso- 

 lated. The organism when. stained and examined micro- 

 scopically appeared as a remarkably short and delicate 

 bacillus, shorter and more slender than the diphtheria 

 bacillus, measuring about 0.8-1.7 fx in length and about 

 0.3-0.4 ft in breadth. When stained it appeared some- 

 what granular, and so resembled somewhat the diphtheria 

 bacillus. Old cultures presented similar involution-forms 

 to those seen in old cultures of the diphtheria bacillus. 

 In general the bacillus resembles the organism found by 

 Afanassiew l and others in cover-glass specimens of 

 whooping-cough sputum, but diners in that spores were 

 seen several times. 



In pure cultures on coagulated hydrocele-fluid the ba- 

 cillus forms a finely granular layer of pearl-white color. 



On agar-agar the cultures are opaque, pearl-white, and 

 occur as a thin layer. 



The colonies upon agar-agar are whitish by reflected 

 light, and straw-yellow or deeper olive-green by trans- 

 mitted light. They are of an irregularly rounded shape 

 and are granular. 



In gelatin puncture-cultures the growth resembles that 

 of the streptococcus, forming along the track of the wire 



1 St. Petersburger med. Woch., 1887, Nos. 39-42. 



