34G The Microscope. 



pieces of the epidermis from the different surfaces of pitchers 

 induced him to try various methods of preparation. Maceration in 

 caustic potash solution of 2 per cent, strength gave admirable 

 results. The pitchers to be macerated were placed whole in beakerg 

 containing the solution, and boiled over a Bunsen flame for from 10 

 minutes to 2 hours. The pitchers of Nepenthes, if young and fresh, 

 had both outer and inner epidermis loosened from the green cellu- 

 lar and fibrovascular systems after about 15 or 20 minutes boiling; 

 old or dried pitchers require 30 to 60 minutes. By floating them 

 aftei-wards in clean water, both epidermal layers covild be detached 

 with great ease. Pitchers of Cephalotus were macerated after 10 to 

 20 minutes' treatment; but those of Sarracenia, Heliamphora and 

 Dai'lingtonia, except when young and tender, required boiling for 

 about 2 hours, with subsequent maceration for 2 or 3 weeks in water. 



In this way not only could long pieces be obtained for con- 

 tinuous microscopic examination of the surfaces, but bottled hand 

 specimens of the entire inner epidermis of Nepenthes could be 

 made, showing clearly to the naked eye the attractive conducting 

 and secreting surfaces, with associated glands. 



Similar treatment of leaves for preparations of hairs, water 

 and air stomata, etc., give equally good results in many cases. — Jr. 

 R. M. Society. 



Resilvering Mirrors. — The Scientific American gives the 

 following method for resilvering mirrors : Clean the bare portion of 

 the glass by rubbing it gently with fine cotton, taking care to 

 remove any trace of dust or grease. If this cleaning be not done 

 very carefully, defects will appear around the place repaired. With 

 the point of a knife cut upon the back of another looking-glass 

 around a portion of the silvering of the required form, but a little 

 larger. Upon it place a small drop of mercury; a drop the size of 

 a pin's head will be sufficient for a surface equal to the size of the 

 nail. The mercury spreads immediately, penetrates the amalgum 

 to where it was cut off with the knife, and the required piece may 

 now be lifted and removed to the place to be repaired. This is the 

 most difficult part of the operation. Then press lightly the renewed 

 portion with cotton; it hardens almost immediately, and the glass 

 presents the same appearance as a new one. 



Notes from American Postal Microscopical Club Note 

 Books. — A. P. Brown recommends the following modification of 

 Tarrant's solution for starches: Gum arabic, selected, about 2 oz. ; 



