insects, be of strips about Vi- inch wide and several 

 inches lon^^, but for larger specimens small vial corks, 

 cut in two at the mid diameter between the ends are 

 more desirable. A sheet of paper the size of the glass 

 is ruled both ways, upon which the box is laid that the 

 intersections of lines may indicate where to place the 

 cork. Dr. Lintner complains of the cork loosening from 

 the glass in a few years. Professor Kellicott has used 

 a mixture of red lead and gold size. Corks set with 

 this mixture in 1878 are still as firm as ever. My 

 boxes cost me just 23^/4 cents each, exclusive of m}-^ time 

 in putting them together. 



If strips of cork 11 inches long are used and placed 

 V^ inch from center to center, the box will contain 2G 

 strips which will make 286 inches of cork, and if the 

 pins are stuck V^ inch apart, the box will contain 1144 

 insects. A parasite can not crawl its length on glass in 

 a vertical position, that in which it should always be 

 kept. The only way in which they can get to the 

 insects is to crawl from off the wood onto an insect, 

 that touches the wood, which they should not be 

 allowed to do ; or they may fall from the upper end 

 onto an insect. 



It is objected that the light will fade some of the 

 colors of the insects. If the boxes are placed in an 

 ordinar}' case or cupboard, as the\^ should be when not 

 in use, this difficulty is overcome. 



Notes on Erysiphe-e, with Chart of Uncinula. By 

 Aug. D. Selby. 



These notes are presented as a continuation of the 

 study of the Ohio Erysiphece, published in the proceed- 

 ings for last year. 



Attention is called in passing, to the reported 

 occurrence of the ascigerous form of Oidium Tuckeri on 

 the grape in France in November last.* 



This is the same as the American Uncinula necator 



36 



