FOUND GROWING IN LIVING ANIMALS. 279 



the scalp was covered with a furfuraceous desquamation, consisting only, as 

 shewn by the microscope, of epidermic scales. On the sixth day, the scabs were 

 of a dirty yellow colour, but not of the peculiar tint or form of the porrigo crust. 

 Only a few pustules remained, and the injected appearance of the skin was gone. 

 On the tenth day, the head was covered with irregular agglomerated scabs, simi- 

 lar to those produced from impetigo. The separation of numerous epidermic 

 scales, constituting a furfuraceous desquamation, also continued. On the twelfth 

 day, I detected for the first time, at the posterior part of the scalp where the hair 

 was most abundant, small bright yellow spots, the size of a pin's head, somewhat 

 depressed below the surface. On removing one of these spots with the point of a 

 lancet, and examining it by means of a biconvex lens of an inch focus, I found a 

 smooth, cupped-shaped, bright yellow capsule, the diameter of which was about 

 55 of an inch. Its margin was continuous with several epidermic scales, which it 

 was necessary to cut or tear through before the capsule could be removed. Hav- 

 ing done this, it was readily separated from the parts below, except where the 

 hair which usually perforates these crusts connected it inferiorly with the dermis. 

 On pulling this out, or cutting it through, the capsule could be removed entire, 

 leaving behind it a reddened inflamed concave depression, corresponding to the 

 convexity of its inferior surface. Its removal gave rise to the effusion of a thin 

 greyish looking serum, which soon concreted on the surface. On placing this 

 capsule in a drop of water, pressing it between two slips of glass, and examining 

 it with a magnifying power of 300 diameters, it was found to be composed of an 

 amorphous mass, in which Avere numerous long-jointed filamentous tubes. These 

 were seen coming from the edge of the capsule, as M. GHUBY has described. 

 (Plate VI. fig. 3.) At this time there was no appearance of beaded filaments, com- 

 posed of round or oval globules. These did not appear until three days later, 

 at first isolated, and then in groups and chains. (Plate VI. figs. 5 and 6.) The 

 further development of the plants, and of the disease, appeared to be exactly as 

 M. GRUBY has described it. 



Observation 2d. In a boy of well marked scrofulous habit, labouring under the 

 Porrigo lupinosa in its most characteristic form, the crusts over the two anterior 

 thirds of the scalp, where it was for the most part bald, were numerous, round, 

 and isolated, but matted together posteriorly where the hah* was still abundant. 

 When examined microscopically the mycodermatous vegetations were immediately 

 detected as in the last case. All the crusts were removed by the application of 

 poultices, and the head rendered perfectly smooth and clean. In three days, a 

 furfuraceous desquamation of the cuticle appeared, which became more and more 

 abundant until the eighth day, when the small bright yellow spots of the porrigo 

 made their appearance, not having been preceded by the formation of any pus- 

 tules. The crusts were removed several times in succession, and the disease 

 again allowed to appear ; but in this case the appearance of the peculiar porrigo 

 crusts was never preceded by that of pustules. 



