592 Microscopic Organisms in Blood and their Relation to Disease, [part hi, 



apply equally to bacillus of hay-infusions, for I have been unsuccessful in witnessing 

 anything like the germination-process in the " spores " of the latter also. Nor were 

 the " spores " which formed in bacilli associated with the anthracoid-blood of the horse, 

 observed to germinate. 



With regard to specific distinctions which have been based on the differences of 

 size which microphytes of this character present — specific distinctions which, in all 

 probability, will be still further advocated in the future — it is of interest to note that 

 the bacilli found in the blood and tissues of animals which, at the period immediately 

 preceding their death, had been perfectly healthy, manifest considerable latitude in 

 this respect. The following extracts from my note-book may serve as illustrations of 

 this, and, at the same time, furnish a brief epitome of the changes which bacilli- 

 filaments undergo under very slightly varying circumstances. The first series of 

 extracts will refer to bacilli of a smaller size than ordinarily seen. The notes run as 

 follows : — " Killed two mice yesterday and examined one of them to-day, 24 hours 

 after death. The red blood-cells from blood taken from the heart fairly well preserved. 

 Numerous short bacilli present — motionless. The spleen also crowded with similar 

 bacilli. They appear to be of a smaller size than are usually met with, the segments 

 averaging only 2-5/a in length by -8 to 1/i in breadth : though, in many of the rods, 

 indications of segmentation could not be detected, or detected only in parts of them. 

 The segments became more evident on drying, so that measurements could be accurately 

 made. The sketch has been drawn accurately to scale {vide Plate XLI, Fig. 6). 

 A drop of aqueous humor was placed on a cover-glass and a needle dipped into 

 the spleen, and then applied to the droplet of humor. The cover was inverted and 

 placed on a glass slide, hollowed in the centre, a little olive oil having been placed 

 along the rim of the hollow to maintain the cover in its position. Another specimen 

 was prepared and mounted on a slide in the ordinary way {i.e., without access to air 

 except along the edge of the cover-glass), and both were set aside until the following 



day." 



The course taken by the latter preparation is described as follows : " The ' ordinary ' 

 preparation of yesterday's note was found to have altered somewhat. At one side of 

 the slide a number of bacterium termo had developed, forming a whitish rim; along 

 with these were staves of the same character as described yesterday, but considerably 

 grown, which were being knocked about in all directions by the bacteria. The greater 

 portion of the preparation had gone on to ' spore ' formation, as figured at a, Plate XLI, 

 Fig. 7. In others the filaments and joints were still distinct and presented a proto- 

 plasmic aspect (6). Many of the filaments were held together by very slender cords, 

 sometimes as if by one comer only, probably owing to a twisting of the tube ; at 

 others the continuation of the tube was distinct (c). [Compare this description with the 

 figures of bacillus anthracis reproduced from Dr. Cossar Ewart's paper, Figs. 43 and 44, 

 page 575.] Here and there filaments could be seen in a transition stage, a ' spore' having 



