1896.] MICROSCOPICAL JOURNAL. 223 



BIOLOGICAL NOTES. 



Plant Lungs. — One of the prettiest microscopical 

 studies is the examination of the lung-s of a plant. Most 

 people do not know a plant has lung-s, but it has, and its 

 lung-s are in its leaves. Examined throug-h a hig-h power 

 microscope, every leaf will show thousands upon thousands 

 of opening's, infinitely small, of course, but each provided 

 with lips which, in many species, are continually opening- 

 and closing-. 



IttEDICAL MICROSCOPY. 



Coffee and Disease Germs. — A year ag-o, a Russian 

 bacteriolog-ist made some experiments for the purpose of 

 determining- the influence of coffee in destroying- disease 

 g-erms. The conclusion was that coffee is to some deg-ree 

 a disinfectant. The disinfectant properties of coffee de- 

 pend, however, not upon the active principle of coffee, or 

 caffein, which it contains, but upon the substances devel- 

 oped in the roasting- of the coffee. It was found that the 

 various substitutes for coffee are also g-ermicides, and, 

 like it, develop disinfectant properties during- the roasting* 

 process. A watery infusion of either coffee or its substi- 

 tutes was found to be capable of killing- the g-erms of chol- 

 era within a few hours, and of typhoid fever in a somewhat 

 long-er time. 



The conclusion should not, however, be drawn from these 

 statements that either coffee or its substitutes are to be 

 considered of value on account of their slig-ht antiseptic 

 properties, as too long- a time is required for the destruc- 

 tion of g-erms by them. — Modern Medicine. 



The Influence of Surrounding Micro-Organisms on the 

 Cholera Vibrio. — Senarelli found cholera vibrios in the 

 water supply of both Versailles and St. Cloud. The 

 former place is practically immune from cholera, but the 

 latter is not so tothe same deg-ree. Seeking- for an expla- 

 nation of the difference between the two cities in this 



