Variola : Pox. 339 



metatarsal region, with more or less (sometimes extreme) lame- 

 ness. On the swollen skin may be detected nodules, which may 

 pass early into vesicles and pustules. The eruption varies, how- 

 ever, as developed on the comparatively hairless lips or nose, or 

 on the densely pilous pastern. 



On the lips, or other part lightly covered with hair, one can 

 easily follow the successive formation of the round nodule, the 

 distinct (sometimes unbilicated) vesicle, with its clear translucent 

 straw-colored contents, and the pustule, which bursts, forming a 

 sore, or dries up forming a dense scab, like that of cowpox. 



On the heels, or on any part thickly covered with hair, the 

 vesicle or pustule is rarely recognized, the exudate on the con- 

 trary takes place mainly on the surface, which becomes encrusted 

 with an abundant yellowish concretion, matting the hairs together, 

 and somtimes literally covering them. This may be very mis- 

 leading to the practitioner who expects to see the succession of 

 fully developed vesicle and pustule, and overlooking the true 

 nature of the malady he may allow it to spread widely in a stable. 



Describing his inoculation cases, Chauveau gives the following 

 successive phenomena : — 



' ' From the fifth to the eighth day the points of inoculation be- 

 come distinctly papular. As far as about the tenth day, the 

 papules eucrease, and become more prominent, taking the form 

 of an extremely wide cone, with a base oi }i to j4 inch. During 

 this period these large conical papules are re.sistant and painful 

 on pressure, but show no elevation nor change in the epidermis, 

 save a slightly reddish reflection in animals with white skins. 

 Afterward supervenes a new stage which may be called the 

 period of secretion. This commences from the ninth to the twelfth 

 day. 1 The epidermis, .slightly raised upon all the papule, sweats 

 "out numerous drops of a limpid, very slightly yellow serosity. 

 These drops soon concrete into yellowish, transparent crusts 

 covering the whole surface of the pustule : — a species of charac- 

 teristic crystallization, very different from the crusts that succeed 

 the vaccine pustules in mare and cow. The secretion, which 

 continues several days, is terminated from the thirteenth to the 

 seventeenth day after inoculation. If then the crust is raised 

 there is exposed a humid, pink, granular surface not projecting 

 beyond the surrounding skin. This surface is hollowed out by a 



