5 2 
Poisonous Arthropods 
40. Same as figure 39, on larger scale. 
through some curious mis¬ 
understanding Goeldi (1913) 
has featured the larva of 
Orgyia leucostigma , the white- 
marked tussock moth, as the 
most important of the poi¬ 
sonous caterpillars of this 
country. Though there are 
occasional reports of irritation 
from its hairs such cases are 
rare and there is no evidence 
that there is any poison pres¬ 
ent. Indeed, subcutaneous 
implantation of the hairs 
leads to no poisoning, but merely to temporary irritation. 
Occasionally, the hairs of certain species of caterpillars find lodge¬ 
ment in the conjunctiva, cornea, or iris of the eye of man and give 
rise to the condition known as opthalmia nodosa. The essential 
feature of this trouble is a nodular conjunctivitis which simulates 
tuberculosis of the conjunctiva and hence has been called pseudo- 
tubercular. It may be distinguished microscopically by the presence 
of the hairs. 
Numerous cases of opthalmia nodosa are on record. Of those 
from this country, one of the most interesting is reported by de 
Schweinit z and 
Shumway (1904). It 
is that of a child of 
fifteen years whose 
eye had become in¬ 
flamed owing to the 
presence of some for¬ 
eign body. Down¬ 
ward and inward on 
the bulbar conjunc¬ 
tiva were a number 
of flattened, grayish- 
yellow nodules, be¬ 
tween which was a 
marked congestion of 
+ mn iiinr'-ti-u-ol 41 - Nodular conjunctivitis in the eye of a child. 
tne conjunctival and DeSchwcinitz and Shumway. 
