THE AMERICAN BOTANIST 149 



Chufa and Nut Grass Different. — Permit me to call 

 attention to a mis-statement on page 134 of the November, 

 1917, issue. Cyperus rotundus is the true nut grass and is 

 never called chufa by people familiar with the plant. The 

 nuts are not "very sweet and edible"; on the contrary they 

 are very bitter and vile to the taste. Since the plant is one 

 of the very worst, if not the worst, of Southern weeds, it is 

 probably cultivated about as much as Canada thistle is in the 

 North. What you say for rotundus is true for the following 

 species, C. csculcutus, which is the true chufa of the South, and 

 is occasionally found in the North. Though a bad weed in 

 some sections, its tubers are sweet and edible, especially when 

 roasted like peanuts. The plant has a limited use as hog 

 food. I studied both of these plants last summer and found 

 a good deal of confusion in botanical literature concerning 

 them; a confusion which should be straightened out. — Albert 

 A. Hansen, Washington, D. C. 



Mushroom Poisons. — The diffusion of mycological 

 knowledge has pretty well disposed of the old idea that there is 

 one mushroom and a large number of toadstools. As a matter 

 of fact there are a large number of mushrooms — hundreds of 

 them — some poisonous and some edible. The poisonous ones 

 may be called toadstools if desired, but they do not differ in 

 any particular from mushrooms and, in some cases, harmless 

 and harmful species are found in the same genus. It is also 

 becoming known that the poison in mushrooms is of various 

 kinds, some easily overcome by antidotes and some almost un- 

 affected by any that we know of at present. One of these, 

 found in Gyromitra esculenta, is a destroyer of the red blood 

 corpuscles, another found in a large number of species is a 

 disturber of digestion. This latter may be removed from 

 suspected specimens by boiling for a few minutes in vinegar 

 and water. A third group of poisons attack both the digestive 

 and nervous systems. Several of the Amanitas have this 

 poison, which is soluble and may be removed from the mush- 



