52 



Poisonous Arthropods 



40. Same as figure 39, on larger scale. 



through some curious mis- 

 understanding Goeldi (19 13) 

 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 simtdates- 

 tuberculosis of the conjunctiva and hence has been called psetido- 

 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 

 Schweinitz 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 nodvdes, be- 

 tween which was a 

 marked congestion of 



tVlp rnniiino-f-iiT-Ql anrl *^- (o) Nodular conjunctivitis in the eye of a child. 



tne conjunctival ana DeSchweinitz and Shumway. 



