206 PA THOGENIC JBA CTERIA. time than is required by the staphylococcus. They did not succeed in producing mumps in animals. In their experience a dog was encountered which suffered from swelling of the parotids, malaise, etc., after playing with a child suffering from mumps. Concerning the diplococcus, it appeared in twos and fours; rarely in larger groups. Each was regularly rounded and about the size of the pus cocci. The colonies are small, white, glistening, distinctly defined, regularly circular spots, at first discrete and of slow growth, gradually coa- lescing. The slow growth is characteristic. In study- ing pure cultures, some gelatin tubes three days after in- oculation were set aside, no growth being noted; three days later the small white colonies became distinctly vis- ible. At ordinary temperatures gelatin is not liquefied until ten or twelve days, and the liquefaction proceeds slowly. A faint white streak appears on potato on the third day, and spreads as a delicate whitish film. The growth upon blood-serum is more rapid than on other media, but the colony is not so distinctly white in color. Litmus milk is changed to pink on the third day and is coagulated. Milk is thought to be an excellent nutrient medium, and a possible ready means of spreading con- tagion. In the paper of Mecray and J^alsh no mention is made of the relation of the cocci to pus cells or other organized constituents of the secretion from which they were obtained; no animal inoculations were done and nothing is said about the reaction to Gram's method of staining or possible motility the cocci might possess. Michaelis and Bein,1 of Leyden's clinic, found a diplo- coccus (previously observed by Leyden in the sputum), which occurred chiefly in the pus cells. In severe cases of the disease, which they studied by culture and micro- scopic section, the organism was not only secured from Stensen's duct, but in 2 cases from the pus of an abscess (parotid ?) and in i case from the blood. 1 Deutsche med. Wochenschrift, May 13, 1897.