BACILLUS PYOCYANEUS. 169 



sipelas lesion, and are placed in the incubator for three weeks. 

 The same flasks are then inoculated with Bacillus prodigiosus 

 and replaced in the incubator for ten or twelve days. At the 

 end of this time the flasks are well skaken and their contents 

 poured into bottles of about one-half ounce capacity. These 

 Dottles are exposed to live steam for one hour. The toxin is 

 injected directly into the tumor mass or into its periphery. 



The best results from the use of this combined toxin have 

 accrued in the treatment of accessible sarcomata. The injec- 

 tion is followed by necrosis and a gradual disappearance of 

 the tumor. Quite a number of cases have been successfully 

 treated in this manner. The serum has, however, proved 

 most successful in the hands of its originator. The experi- 

 ence of the vast majority of the profession with its use has 

 not warranted its continuance, and it has now been practically 

 abandoned except by a few. Its use is restricted largely to 

 inoperable cases, with the hope that some good may result. 



Bacillus Pyocyaneus. 



Strictly speaking, this is not a pus-producing germ, but it 

 is frequently found in pus, to which it imparts a blue or green 

 color. For this reason it is always described with the pus 

 germs. It has also been found on the skin, especially in the 

 axillae, in the external auditory canal, and in the intestinal 

 mucus. It is possible that very large numbers of the organ- 

 ism may induce suppuration. 



Biology and morphology : The Bacillus pyocyaneus is a very 

 small, slender, and exceedingly motile bacterium, with rounded 

 ends, and possessing a single terminal flagellum. It is 0.3 JJL 

 in length and 1.2// in width, and usually occurs singly, 

 although occasionally it forms short chains of four or five. 

 It does not sporulate, reproducing itself by fission. It is a 

 facultative anaerobe, although developing best in the pres- 

 ence of oxygen. The anilin dyes stain it readily. It is 

 decolorized by Gram's stain. Its temperature optimum is 

 indefinite, as it grows equally well at either the room or body 

 temperature (Fig. 71). 



On gelatin plates it forms small flat round colonies of a 



