riBBIO NASALI8. 375 



tinated, and of these, it is at least questionable whether 

 they may not be looked upon as cholera vibrios, as in the 

 case of the Vibrio berolinensis. 



Also here the negative result of the test (absence of 

 effect by a serum in dilution of 100, which produced a posi- 

 tive effect against true cholera vibrios when diluted 120 to 

 150 times) allows an exclusion of cholera vibrios ; a posi- 

 tive marked result makes the diagnosis more sure. With a 

 positive but weak reaction the diagnosis of cholera, on the 

 contrary, is not entirely certain ; for example, with a tardy 

 action in dilution of 50 times, while true cholera vibrios are 

 promptly agglutinated by dilutions of 80 to 100. It would 

 be best to place no dependence at all upon reactions which 

 only occur in concentration above one in fifty and after 

 half an hour. Compare also Mann (A. H. xxxiv, 179). 



Occasionally also the testing of the agglutinating action 

 of the serum upon true cholera vibrios in a case of cholera 

 during the disease or convalescence may make the diag- 

 nosis more certain. 



Some Other Vibrios Which Are Not to be Confounded 

 with the Vibrio choleras. 



Vibrio spermatozoides. Lbffler (C. B. vii, 637). 



This remarkable variety, occasionally found in turnip-cabbage 

 infusion by LoiBer, and photographed by him, is characterized by 

 powerful terminal flagella (56, vi) ; the latter disappear or are very- 

 delicate upon turnip-cabbage gelatin, but return partially upon rein- 

 oculation into turnip-cabbage infusion. The organism presents Y- 

 shaped forkings ! (See the note, p. 352. ) 



Vibrio nasalis. Weibel 1 (C. B. ii, 466; iv, 225). 



(Plate 56.) 



According to Weibel, a very interesting variety. "We have not 

 studied it. 



Microscopically : In nasal mucus, thick vibriones (56, 11) ; in 



^ Also of interest are the following closely related organisms, which 

 have been described by Weibel {I. c. ) and grow upon gelatin with a 

 yellow color and without liquefaction: Vibrio flavus Weibel, aureus 

 Weibel, and flavescens Weibel. Regarding these varieties, which do 

 not come seriously into question in the differential diagnosis of the 

 Vibrio cholerse, the original must be consulted. 



