1900] MICROSCOPICAL JOURNAL 79 



perature is the most important factor iu the dwarfing of 

 alpine plants. The assimilative power per unit of sur- 

 face of the leaf showed a great increase (Corapt. rend. 

 128: 1143) in the specimen grown under alpine condi- 

 tions. 



Lake Flora. — Prof. G. E. Stone who has puhlished a 

 short paper on the Flora of Lake Quinssigamond found 

 quite a large number of alga?. The most satisfactory pre- 

 serving fluid is glycerine one part, water two parts, alco- 

 hol three parts. L. H. Pammel. 



Miscellaneous Notes on Microscopy. 



JOHN. H. COOKE, F. h. S., F. G. S. 

 Carbolic Acid. — Collections of material kept in damp 

 places, or in a moist atmosphere, are very liable to mould 

 and under such conditions it is difficult to avoid this evil. 

 Carbolic acid is recommended, but Mr. Ashmead,who has 

 kept a large collection in the moist climate of Florida, has 

 found the use of napthaline much more satisfactory. Mr. 

 H. H. Smith, who has had more extensive experience in 

 the tropics, prefers the carbolic acid. Mouldy specimens 

 may be cleaned by washing witli carbolic acid applied 

 with a fine camel's hair brush. 



Cement. — Asphalt, dissolved in spirits of eturpntine, 

 is one of the best mediums for sealing cells, and, provided 

 that no traces of the mounting medium are left on the 

 edges of the cells before applying the solution, the ce- 

 ment will keep unchanged for years. 



Diatoms. — The propagation and growth of diatoms are 

 influenced to a marked extent by meteorological condi- 

 tions. They increase most rapidly during those seasons 

 of the year when the water is in circulation throughout 

 the vertical currents. The vertical currents keep the dia- 

 toms near the surface, where the light stimulates their 

 growth, and where there is an abundance of air and food. 



