220 ENTOMOLOGICAL SOCIETY 



Mr. Schwarz exhibited specimens of Trichotheca vagans 

 (Chrysomelidae, Eumolpini) and pointed out that the femoral 

 tooth of this species is merely a sexual character, the female 

 being entirely unarmed. He also showed specimens of Xan- 

 thonia lo-notata and villosula having a very small, but distinct 

 femoral tooth. It would appear, therefore, that the two genera, 

 at least as far as the species in our fauna are concerned, are 

 hardly distinct, the only difference left being the somewhat 

 longer antennae in Trichotheca. 



Mr. Schwarz also presented the following paper : 



VERDIGRIS IN COLEOPTERA. 



BY E. A. SCHWARZ. 



Every entomologist knows what verdigris is. He will have 

 found by experience that it is an almost greater destroyer of 

 valuable pinned specimens than the Anthreni and other 

 museum pests. Several remedies and preventives have been 

 recommended: i. The washing of the affected specimens with 

 chloroform or some ether. This is, however, only a temporary 

 remedy and involves, moreover, for the possessor or keeper of 

 a large collection incessant work. 2. Not to pin anything, 

 but to. glue even large specimens on to card paper. This pre 

 cautionary measure is almost universally carried out, but has, 

 of course, many drawbacks, especially in the larger-sized 

 specimens. 3. To use iron pins instead of the common brass 

 pins. This is, of course, a perfect protection, but unfortunately 

 these pins are on account of their softness difficult to handle, 

 and on account of their greater roughness almost unfit for pin 

 ning specimens with a hard covering. 4. To use heavily 

 silver-plated pins. This is no doubt also a good preventive, 

 but such pins do not appear to be readily obtainable, and as a 

 matter of fact are not used with us. The Carlsbad pin appears 

 to be less subject to verdigris than the Klager pin, but the 

 former is objectionable on account of the too soft point. The 

 Klager pins are most commonly used with us, but it would 

 appear to me that in former years they were of a better quality 

 and less subject to verdigris than they are now. With the 

 Vienna pins, the Deyrolle pins and the English pins I have had 

 no experience. 



In the preservation of Coleoptera I have adopted the method 

 of mounting on points of card paper all such species, even those 

 of pretty large size, which, in the experience of others and my 

 self, are subject to verdigris. The families which are not subject 



