Henle (quoted by Ellenberger) states that a spermatozoon under favorable conditions travels at the rate of twenty-seven millimeters in seven and one-half minutes, which makes three and five-tenths millimeters per minute. This is about sixty times the entire length of the spermatozoon, and twenty-one centimeters in an hour. Forward motion is also more pronounced when the swim is against the current, such as is produced by the cilia of the oviduct. It has been demonstrated that feebly motile sperms become very actively motile when placed on the mucosa of a fresh Fallopian tube. TECHNIQUE The material used in the work came from abattoir animals, bull calves and adult bulls raised in the department herd, and sires upon which clinical observations had been made by various veterinarians in the field. Semen samples, many of which were sent in, were collected as often as possible after the method described by Williams (16). The genital organs were removed with as little chance of contamination as possible, and taken or sent to the laboratory where the examinations were made soon after arrival. All cultures were made by searing the surface carefully, tearing out a small portion of the tissue with sterile forceps, and placing it upon the media. In most cases, however, where fluids were present, tubes were inoculated with the material which had been drawn off with a sterile pipette. As stated by Carpenter (9), in his work on the female genital tract, the organisms usually live in the depths of the tissue. The media used principally were glucose glycerin agar (glucose 1 per cent, glycerin 3 per cent); plain agar, both with a pH value of 7.4, and Loeffler’s blood serum. Small amounts of sterile blood serum or defibrinated blood were added to most of the agar slants to insure better growths of streptococci when present. All tubes, to which the serum had been added, were incubated for forty-eight hours before inoculation to insure absolute sterility. After inoculation, the agar tubes were sealed with sealing wax to give a partial oxygen tension which was quite necessary in isolating the streptococci. The growth of other organisms was by no means hindered by the procedure, for one tube from each organ was often left unsealed. Incubation was at 37° C, and the routine method of examining the tubes was identical with the method of Carpenter (9). Whenever possible, a sample of blood was obtained from the animal either before, or at the time of slaughter, for agglutination with _Bact. abortum_ antigen. Extracts from the seminal vesicles, testes, and epididymes were injected into the guinea pigs and examined at the end of four to six weeks for the presence of _Bact. abortum_.