224 ENTOMOLOGICAL SOCIETY 



that oiliness was almost invariably accompanied by verdigris. 



Prof. Riley said that oiliness of water-beetles was superficial 

 and was of a sticky nature, and seemed to be different from the 

 oiliness of other insects. 



Mr. Austin in explanation of the nature of verdigris said 

 that the decomposition of insects results in the formation of both 

 alkalies and acids, and the combined action of these results in 

 the formation of copper soap or verdigris. 



Mr. Stedman reported the results of certain investigations 

 which he had been conducting on the character of the covering 

 of the gills of aquatic larvae of Diptera, stating that quite con 

 trary to the formerly accepted idea the gills are covered with a 

 thin chitin rather than a non-chitinous membrane. This fact 

 he had established to his own satisfaction in the case of several 

 species, and proposed to continue his observations and present 

 full report later. 



OCTOBER IST, 1891. 



President Marx in the chair. Fourteen members and five 

 visitors present. 



Messrs. B. W. Doran, A. G. Masius, F. C. Test and W. T. 

 Swingle were elected active members of the Society ; Messrs. 

 H. K. Weed, William H. Harrington and K. A. Popenoe were 

 elected to corresponding membership. 



Mr. Heidemann presented the following : 



NOTE ON THE FOOD-PLANTS OF SOME CAPSID^ FROM 

 THE VICINITY OF WASHINGTON, D. C. 



BY OTTO HEIDEMANN. 



On my excursions in the vicinity of Washington I have, 

 during the past two years, paid considerable attention to the 

 food-habits of Hemiptera-Heteroptera and more especially of 

 the family Capsidse in which I am particularly interested. Of 

 the many notes which I have thus accumulated I venture to 

 place herewith on record such as relate to Capsids affecting 

 some of our forest and shade trees. The species have been 

 kindly determined for me by Prof. Ph. R. Uhler, of Baltimore. 

 Unfortunately there are among them many undescribed species, 

 and the following list contains quite a number of Prof. Uhler 's 



