ECTHYMA. 145 



I was tormented for six weeks, when the only indication of 

 the pre-existing eruption was the brown appearance of the 

 skin where the pustules had existed. Early in March, how- 

 ever, at a spot on the inside of my right arm, just above the 

 elbow, where the redness had not completely subsided, a 

 large boil formed, which, on being opened, was found to con- 

 tain a considerable slough. This boil was attended with 

 much pain, and healed very tardily. Two other persons that 

 attended the cow, including one of my students, suffered in a 

 similar manner. Many cases are on record which indicate 

 the dangers incidental to exposing the arm to the contact of 

 the vagina, and the acrid fluids it contains, in cases of diffi- 

 cult labour in the lower animals. 



HEEPETIC AND BULLOUS ERUPTIONS. 



Bullse are large vesicles which differ from the eruptions 

 already described in little more than size. They characterize 

 the group of diseases now to be spoken of, and clusters of 

 bullas, or globular vesicles, are found studding patches of 

 inflamed skin. The difference between herpes and pem- 

 phigus is established by the relative size of the bullse or 

 blebs, which are always smallest in herpes, and, altogether, 

 the latter disease is the mildest of the two. Pemphigus is 

 known only as it occurs in man. 



The term ' tetter ' is popularly used for herpes, and there 

 are many forms of this eruption. 



Human physicians divide herpes into the phly ctenoid 

 group and circinate group. The first " is characterized by 

 the irregularity of form and distribution of the clusters ; it is 

 typified by the variety herpes phlyctenodes, and embraces all 

 the local forms. The circinate group, on the other hand, is 

 remarkable for the circular arrangement or form of its clus- 

 ters; hence the herpes zoster consists of irregular clusters 

 VOL. n. 3D 



