300 INFECTIVE DISEASES. 



affected with the eruption on the teats. Fatal effects also result 

 when the milk is administered to young pigs. 



It has been stated that no injurious consequences arise from the 

 consumption of the milk by human beings, but there is abundant 

 evidence to the contrary, and the conflicting opinions probably arise 

 from the fact that milk is seldom drunk direct from the cow, and 

 rarely in an undiluted form. Hertwig experimented upon himself 

 with milk freshly drawn from a cow with the eruption. He drank 

 a pint, and two days afterwards experienced slight fever, restless- 

 ness, and headache. The mouth was dry and hot, and there was 

 tingling in the skin of the hands and fingers. These symptoms 

 continued for seven days after taking the milk. On the ninth day 

 vesicles had formed on the tongue, principally on the edges, and on 

 the mucous membrane of the cheeks and lips (the largest being 

 about the size of a lentil). They were yellowish-white in colour, and 

 contained a whitish turbid liquid, which flowed when the vesicles 

 were pricked with a needle. At the same time a number of vesicles 

 developed on the hands and fingers ; and most of them at the 

 time of their first appearance were the size of a millet seed. They 

 were firm to the touch, yellowish -white, and occasioned a slight 

 tingling. The vesicles of the mouth increased in size and eventually 

 broke, and the epithelium detached itself completely from the affected 

 parts, leaving dark red spots, which disappeared gradually. The 

 slight fever present during the first days ceased after the appearance 

 of the eruption ; but from this time, until the disappearance of 

 the red spots, Hertwig felt a continual burning pain in the mouth, 

 and speaking and deglutition caused considerable uneasiness. On 

 the lips the vesicles dried up, and were covered with thin brownish 

 crusts, which fell off ten days after the appearance of the first 

 vesicles. The vesicles which developed on the hands ran a slower 

 course. From the tenth to the thirteenth day they filled with a 

 liquid, like turbid lymph. They were large and confluent, and 

 finally broke and dried up. 



Bacteria in Foot-and-mouth Disease. Klein in 1885 isolated 

 from the vesicles a streptococcus which in its microscopical and its 

 cultural characters on gelatine, agar and blood serum resembled 

 Streptococcus pyogenes. Minute differences in the size of the 

 colonies and in their rate of growth, and in the character of the 

 chains, were observed 011 making comparative cultures with 

 Streptococcus pyogenes from a human source, but no comparison 

 was made with Streptococcus pyogenes from acute suppuration in 

 cattle. Baumgarten regarded this micro-organism as Streptococcus 



