4 ?. THOMPSON YATES LABORATORIES REPORT 
Bacillus Typhi Abdominalis 
/. Motility 
1 p.c. Only the shorter forms are motile, and the movement is chiefly 
rotatory. 
2 p.c. The movements are most active, and the motility is not confined 
to the short forms. 
3 p.c. A greater number of the bacilli are actively motile. 
4 p.c, 5 p.c, 6 p.c. The bacilli are actively motile in each percentage. 
77. Morphology 
A. Hanging drop. — The short forms preponderate. There are a few long 
rods and filaments. Most of the bacilli have a beaded appearance, and resemble a 
row of cocci. The long forms are segmented, and the segments appear to be 
composed of cocci. As the percentage of bile salts increases the long forms disappear. 
B. Stained preparations. — The appearance of individual bacilli is much the 
same in each percentage. The longer forms are segmented into chains of very short 
bacilli, and some of the latter appear square-shaped, owing to the extreme ends not 
taking up the stain. 
Bacillus Coli Communis 
/. Motility 
1 p.c. Actively motile. 
2 p.c. Motility about the same. 
3 p.c. Slight decrease in motility. 
4 p.c, 5 p.c, 6 p.c Motility decreases with the increased percentage of bile salts until 
it is doubtful whether any of the bacilli are motile. They shew a tendency to ' clump.' 
II. Morphology 
A. Hanging drop. — i p.c. The bacilli are not to be distinguished from the 
B. t. a. except in that the short forms have a more oval appearance. 
2 p.c to 6 p.c With the increase in amount of bile salts the length of the 
bacilli decreases until they appear to be cocci and very short rods. 
B. Stained preparations. — The staining is very irregular. Much more so than 
in the case of B. t. a. Frequently the ends of a bacillus do not stain and are somewhat 
swelled, while in the centre is a very short stained portion which often looks like a 
coccus. 
A bile salt potato juice gelatine was used for plate, stab, and slant cultures, but 
there was nothing characteristic, either in the mode of growth or in stained preparations, 
except in the case of one strain of B. c. c, which always, after 24 hours' growth, 
showed many huge fantastic-shaped involution forms which stained deeply. Many 
other strains were grown, but the same result was never obtained. Lactose, glucose, 
and sucrose were added to the gelatine and used in slant cultures, but no characteristic 
differences were visible. 
