SPIROCHAETOSIS IN MAMMALS 309 
Spirochaetosis of cattle. In 1902, Theiler found  spirocheta 
(spirillum) in a few cattle in South Africa. The animals were suffer- 
ing with “red water’? with possibly one exception. He made a 
number of inoculations with the blood of animals infected with 
spirocheta with negative results. He believed, however, that they 
were the cause of the illness in cattle. The organism was named by 
Laveran S. Theileri after its discoverer. The following description of 
the organism is quoted from Theiler’s report: 
“The microérganism in question is a typical spirillum, and varies 
considerably in its length. The longest microbes measure from 20 to 
30%. They are somewhat thinner at both ends, otherwise the thick- 
ness is about the same throughout the whole length—viz., about .25 
to .40U. The corkscrew-like forms are, as a rule, predominant, but 
there are other forms which are atypical in appearance and also 
shorter. For instance, the parasite may show itself as a simple curved 
line without any spiral curves, representing sometimes the shape of S; 
it may also be completely doubled up, both ends may meet and take 
the shape of a ring, or both ends may cross each other and also form a 
loop. These loops may be of different shapes and sizes. Double 
loops may also be found. It is somewhat difficult to describe all the 
various forms, but they can be easily imagined, considering that the 
spirillum is a very flexible and agile parasite. 
“In preparations made by placing a cover-glass on a drop of fresh 
blood the microérganisms are easily detected. Some of the red 
corpuscles show a slight irregular motion, and when closely watched 
it may be noticed that this disturbance may proceed in a certain 
direction, or again whirl round in the same place. When examined 
under a high power (1-12th inch obj.) the agile spirillum is usually 
seen attached to one or more red corpuscles. Sometimes it is curled 
all round a red or white corpuscle. As soon as the organism becomes 
free and begins to travel through a clear space, a characteristic 
undulating movement is visible, which continues until it finally 
attaches itself to some other blood corpuscle. This motion may be 
noticed for some time; it then becomes relaxed, and finally slackens 
down completely. I have observed the movements in preparations 
which were twenty-four hours old. 
“Staining of the organism may be obtained with any of the aniline 
dyes used in bacteriology, viz., methylene-blue, fuchsin, thionin. 
Good preparations were obtained with Laveran’s modification of 
Romanowsky’s stain, and also with Azur II. In using the last two 
