120 THE ROYAL SOCIETY OF CANADA 



on only the first plate, where the two forms were found together. 

 This same method and procedure was again followed at 50° C, 

 55° C. and 60° C, but there was no growth at either of the last two 

 temperatures, and again the two forms developed together when 

 heated at 50° C. 



Still another attempt was made to secure a pure culture. A 

 fairly heavy suspension was made from the red growth in 16 per cent, 

 solar salt solution, and well shaken. Several successive dilutions 

 were then made until a wet preparation under the microscope con- 

 tained not more than one form in a field. Using a 1 mm. loop platinum 

 needle, drops were made from this last dilution on salted codfish agar 

 plates. This method, however, proved no more successful than 

 preceding experiments in isolating a single form. 



It seemed, therefore, that: 



1. These two organisms were impossible to separate, or, 



2. That the organisms had considerable mutability of form and, 

 after a long series of experiments, we were inclined to think that this 

 organism is extremely pleomorphic. The reasons for this belief are: 



1. Only one type of colony appears on the plates. 



2. Isolation of numbers of these on sloped agar or on 16 per cent, 

 codfish broth, containing a piece of filter paper half in and half out 

 of the medium, shows red growth which, on microscopical examination, 

 gives pleomorphic types. 



3. By transferring alternately from agar to broth and from broth 

 to agar, and by growing in various salt percentages, we obtained a 

 great many intermediate forms. 



4. Further, we think that the organism passes through a sym- 

 plastic stage similar to that described by Lohnis. Further informa- 

 tion on this will be given under the head of "Morphological Char- 

 acteristics." 



4. Morphological Characteristics. 



The life cycle of the red organism is an interesting one on account 

 of its pleomorphism. It occurs as spheres and also as long rods, the 

 former averaging 2-3 ix in diameter and the latter from 1.0-1.6 n in 

 width and as long as 15 ix. Between these two extremes many 

 intermediate forms may be found, differing in diameter, length and 

 shape- — oval, amoeboid, clavate, cuneate, truncate, pointed, spindle, 

 club, pear shape, irregular, etc. These changes have been noted by 

 observations of hundreds of different examinations from many 

 sources, and in different culture media and over a period of a year. 



