Nettling Insects 



53 



416. Section through one of the nodules showing the cater- 

 pillar hair. DeSchweinitz and Shumway. 



episcleral vessels (fig. 41 a). Twenty-seven nodules could be differ- 

 entiated, those directly in the center of the collection being some- 

 what confluent and 

 assuming a crescen- 

 tic and circular ap- 

 pearance. The nod- 

 ules were excised 

 and, on sectioning, 

 were found to be 

 composed of a layer 

 of spindle cells and 

 round cells, outside 

 of which the tissue 

 was condensed into 

 a capsule. The 

 interior consisted of 

 epithelioid cells, be- 

 tween which was a 

 considerable inter- 

 cellular substance. Directly in the center of a certain number of 

 nodules was found the section of a hair (fig. 416). The evidence 

 indicated that the injury had resulted from playing with caterpillars 

 of one of the Arctiid moths, Spilosoma virginica. Other reported 

 cases have been caused by the hairs of larva? of Lasiocampa rubi, 

 L. pini, P or their ia dispar, Psilura monacha and Cnethocampa 

 processioned, 



Relief from Poisoning by Nettling Larvae The irritation from 

 nettling larvae is often severe and, especially in regions where the 

 brown-tail abounds, inquiries as to treatment arise. In general, it 

 may be said that cooling lotions afford relief, and that scratching, 

 with the possibilities of secondary infection, should be avoided, in 

 so far as possible. 



Among the remedies usually at hand, weak solutions of ammonia, 

 or a paste of ordinary baking soda are helpful. Castellani and Chalm- 

 ers recommend cleaning away the hairs by bathing the region with 

 an alkaline lotion, such as two per cent solution of bicarbonate of 

 soda, and then applying an ointment of ichthyol (10%). 



