169 
OBSERVATIONS ON A FEW CASES OF PORRIGO. 
tules, by tlie want of any peculiar inflammatory appear¬ 
ances around these achores, and by its occurrence generally 
in detached more or less irregularly circular spots, consti¬ 
tuting what is vulgarly known as Ringworm. Such is P. 
scutulata. 
Its transference from animal to animal, and from animal to 
man, is so simple and so likely to take place that the utmost 
care is necessary to prevent its spread. I shall just mention 
two out of many instances to this effect. 
In the autumn of 1869 I was consulted about some young 
cattle affected with P. scutulata , and I prescribed the usual 
remedies. On calling at the farm about a week after I found 
That two young horses, a seven year old half-bred mare, 
and the boy ivlio attended the horses and cattle, had all 
become affected with the disease, having most undoubtedly 
received the contagion from the previously diseased cattle. 
The diseased spots were on the inside of the boy's arm, 
between the wrist and elbow. 
On another farm, some three miles from this, the herd-boy 
caught the disease from some young cattle under his charge. 
The back of one hand and the outside of the arm in this 
case became affected. A little girl, the farmer's grandchild, 
unfortunately caught the contagion while romping with the 
herd boy at meal times. Besides several other diseased 
spots there was a very large one on the centre of this girl's 
forehead; the effects of the disease on this spot were visible 
for more than a year, having been extremely difficult to 
eradicate. 
I may here remark, what has often attracted my attention, 
that the superincumbent crust of P. scutulata are darker in 
colour in the human subject than in the lower animals, and 
are not so thick or deep as those of P. favosa. 
During the month of November, 1871, two very interest¬ 
ing cases of P. decalvans came under my notice; the 
one in a hare ( Lepus timidus), and the other in a young 
retriever dog. Luckily, I was enabled to make a close 
examination in both animals with a pretty strong object 
glass. 
This variety of Porrigo is the most singular of all, having 
very few distinctive characteristics common to the others, 
and yet without doubt originating in a similar parasitical 
cause. Like the other varieties, it often occurs in nearly 
circular spots; unlike the others, however, these spots are 
almost invariably void of the usual so-called pustular eruption 
or achores: at any rate, I have never met with them of even 
the most minute description. There being no achores , and 
