ZOOLOGY AND BOTANY, MICEOSCOPY, ETC. 137 



are, on the other hand, fixed by a solution of gelatine, to which some 

 alcohol is eventually added, in order to assist the spores in penetrating 

 it. The relative value of the different processes for any particular 

 species must, however, frequently be determined by actual experi- 

 ment. 



Simple and Speedy Method of Staining Animal and Vegetable 

 Sections.* — After cutting the sections, wash them in water, and allow 

 them to soak for a while. 



Transfer them to a solution of anilin violet in commercial acetic 

 acid, the solution to be of the following composition : — 



Anilin violet 1 part. 



Acetic acid 300 parts. 



The sections are to be left in the solution until sufficiently stained, 

 which may be determined by removing them from the solution to 

 clean water. If sufficiently blue, they are then ready to be mounted. 

 If not sufficiently coloured, return to the solution. 



The sections are mounted, after staining, by transferring them to 

 a clean glass slide, draining off any excess of fluid, and adding a drop 

 of solution of acetate of potash of the following strength : — 



Acetate of potash 1 oz. 



Water i oz. 



Cover, and fasten the cover with varnish, permanently if wished. 

 The advantages of this method are its simplicity and the beauty of 

 the results attained ; the disadvantages are that the specimens may 

 fade within a year or two. 



This method is taken from Orth's recent work on histology, 

 and is one strongly recommended for demonstrating the structure of 

 cartilage. 



Staining and Mounting Pollen .f — At a recent meeting of the 

 New York Microscopical Society, some slides of stained pollen were 

 exhibited (the preparation of the Eev. J. T. Brownell), which are said 

 to have been of special excellence. 



The process of preparation was as follows : — A small quantity of 

 pollen having been placed on the centre of the slide, a small drop of 

 staining fluid (anilin dissolved in alcohol) is placed upon it. Then 

 wash by dropping on pure alcohol until all traces of sediment or of 

 stains upon the glass among the pollen grains are washed away. 

 Wipe clean with a dry cloth drawn over the end of a pointed stick, 

 turning the slide rapidly on the turntable. When thus cleaned and 

 quite dry, put on a drop of spirit of turpentine, and then the balsam 

 and cover. 



A few kinds of pollen are distorted by the action of alcohol. 

 Some of these can be stained by the use of an ammoniated solution of 

 anilin. Those that will not bear this solution may be mounted 

 unstained. 



* Amer. Men. Micr. Journ., i. (1880) p. 143. 

 t Ibid., p. 206. 



