1894 THE MICROSCOPE. 15 5 



Leaves of Deutzia. — Elaborate directions are often given 

 for the preparation of slides of Deutzia leaves. Nothing can 

 excel a slide made by simply pressing and drying the leaves and 

 mounting tliem as opaque objects. 



The numl)er of points to the stars vary on the different sides 

 of the leaf. The stars polarize nicely, but as a polarizing objects 

 should be prepared by removing the cuticle and mounting it 

 with the stars as a transparent object. 



A Dissecting Microscope. — For good work in mounting, a 

 dissecting microscope is an almost indispensable accessory. 

 Fii.e instruments of this kind are supplied by dealers. The 

 beginner, with the exercise of a little ingenuity, can improvise a 

 serviceable instrument for the purpose. The essentials are a 

 stage to work on, a simple lens held by a pillar, and a mirror 

 to cast light upon the object. 



The lens should be adjustable for focus. A reading glass or a. 

 set of cheap lenses will do the work, ^[uch magnification is not 

 proper or requisite. The same thing may be accompl;sbed with 

 a pair of watch-maker's glasses fixed to the eyes while dissect- 

 ing. Without some sort of arrangement, preparations will be 

 clumsy and the most beautiful and instructive parts ol a speci- 

 men will generally be obscured or neglected. 



Leaf Fungi. — The simplest and probably the best way to 

 keep leaf fungi for the microscope is to dry and press the leaves, 

 with the fungus, and then wrap the specimens in papers, re- 

 cording on the paper the name of the specimen, the locality 

 where found, and the kind of leaf on which the specimen is 

 growing. Tiie leaves can be used as opaque objects and will 

 exhibit the iungus in a natural condition ; by removing a few 

 spores with a spatula, placing them in a drop of water aild ex- 

 amining them with a quarter-inch objective they will appear to 

 the best advantage. Mounting is apt to shrivel and distort the 

 spores and give but a faint idea of the natural object. 



Dark Ground Illumination. — This may be produced with- 

 out any accessory by simple using oblique light upon a trans- 

 parent object. Set the microscope sidewise upon the table, 

 turn the mirror obliquely and set the lamp so that the rays of 

 light will strike the concave mirror. Butterfly scales, pollen, 

 a living cyclops and thousands of other objects are beautiful 



