OF WASHINGTON. 223 



badly, notably Notoneda. He stated that the fact of verdigris- 

 ing being invariably associated with endophytous larval life 

 was very interesting, and he believed it to be accounted for by 

 such species having a preponderance of oily or fatty matter. 

 With reference to Mr. Schwarz's objections to iron pins on 

 account of their softness and clumsiness, he stated that he had 

 been impressed with the freedom of a collection mounted on 

 iron pins from verdigris, referring to the collection of Mulsant 

 in France, and stated that if the pins were properly made they 

 can be safely used. The insertion of the pins in hard-bodied 

 Coleoptera may be aided by first piercing the beetles with a 

 sharp-pointed needle, after which the iron pin may be safely 

 inserted. He would recommend the use of iron or black pins 

 wherever there was a tendency to grease, and as a consequence 

 to verdigris. 



Mr. Howard asked how soon after pinning verdigris appeared. 



Mr. Schwarz replied that in specimens of Donacia glued to 

 triangles, verdigris began to make its appearance in about four 

 weeks. Other pinned specimens were very badly verdigrised 

 within less than four weeks. Mr. Schwarz also urged another 

 objection to iron pins, viz., that it is impossible to remove the 

 pin, should this at any time become desirable, without injuring 

 or ruining the specimen. 



Mr. Howard made some inquiries as to nature and cause of 

 verdigris, and asked if it were not the result of the action of 

 the acid resulting from decomposition of the oily matter in the 

 insect. 



Mr. Schwarz said that oiliness was not always accompanied 

 by verdigris, mentioning in this respect certain water-beetles 

 which are oily, but which never verdigris. 



Prof. Fernow said that verdigris undoubtedly resulted from 

 the effects of the acids, and recommended the washing of the 

 insects with an alkali to prevent verdigris. He also said that 

 if aluminium pins were used verdigrising would not ensue. 



Prof. Riley referred to Mr. Schwarz's statement that oiliness 

 is not necessarily accompanied by verdigris, and asked for the 

 experience of members. 



Mr. Pergande said that Pyralid and Tortricid moths which 

 grease badly also verdigris badly, and that it was his experience 



