318 INFECTIVE DISEASES. 



same kind of central and marginal character. They appear of 

 various sizes, from that of a pin's head, evidently of a later date, 

 either acuminated or depressed, to that of an almond or a filbert, or 

 ever larger. Dark brown, or black, solid, uniform crusts, especially 

 on the udder near the base of the teats, are visible; at the same time, 

 some much larger are observed on the teats ; these, however, are 

 less regular in form and less perfect. Some are nearly detached, 

 others quite removed, exhibiting a raw surface with a slight central 

 slough. On the teats, the crusts are circular, oval, oblong, or 

 irregular ; some flat, others elevated, some thin and more trans- 

 lucent, being obviously secondary. The appearance of the disease 

 in different stages, or at least the formation of a few vesicles at 

 different periods, seems very evident. The swollen, raw, and en- 

 crusted teats seem to produce uneasiness to the animal only while 

 subjected to the tractions of the milkers, which it would appear are 

 often nearly as effectual as usual." Referring again to the character 

 of the vesicle, Ceely says, that " those fortunate enough to have an 

 opportunity of watching the disease in its progress may observe 

 that, when closely examined, they present the following characters : 

 In animals of dark skin, at this period, the finger detects the 

 intumescent indurations often better than the eye, but when closely 

 examined the tumours present at their margins and towards their 

 centres a glistening metallic lustre or leaden hue ; but this is not 

 always the case, for occasionally they exhibit a yellowish or yellowish- 

 white appearance." 



In describing the crusts in detail, Ceely says that " large black 

 solid crusts, often more than an inch or two in length, are to be 

 seen in different parts of these organs, some firmly adherent to a 

 raw elevated base, others partially detached from a raw, red, and 

 bleeding surface ; many denuded, florid, red, ulcerated surfaces, with 

 small central sloughs secreting pus and exuding blood, the teats 

 exceedingly tender, hot. and swollen. ... In some animals, under 

 some circumstances, this state continues little altered till the third 

 or fourth week, rendering the process of milking painful to the 

 animal, and difficult and dangerous to the milker." 



" In many, however, little uneasiness seems to exist. The parts 

 gradually heal ; the crusts, although often partially or entirely 

 renewed, ultimately separate, leaving apparently but few deep 

 irregular cicatrices, some communicating with the tubuli lactiferi, 

 the greater part being regular, smoothly depressed, circular, or oval." 



Ceely illustrated his classical memoir with a series of valuable 

 coloured drawings. One plate is a faithful picture of the disease on 



