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THE AMERICAN BOTANIST 



portions of the plant, but only recently it has been found infest- 

 ing the roots as well. When the roots are attacked they become 

 brown and shrunken but do not become soft as they do when 

 attacked by other kinds of rot. As in the case of other fungous 

 pests, spraying with Bordeaux mixture has been found to be 

 the best preventive, but the removal and destruction of the 

 tops in autumn and even burning over the bed, late in the year, 

 are additional helps of value. 



False Toad-flax Harmful. — The species of false toad- 

 flax {Cornandra iimhellata and C. pallida) have long been 

 known as hemi-parasites which draw part of their food from the 

 underground parts of other plants to which they attach them- 

 selves by means of hemispherical disks or holdfasts fonned by 

 the roots. They are probably most frequently parasitic on 

 various species of blue-berry { Vacciniuin) but they are known 

 to attack some fifty other species including such diverse forms 

 as herbs, shrubs and trees. As parasites, however, they cause 

 little injury. Their harmfulness comes from their harboring on 

 their leaves one stage of a very destructive blister rust (Peri- 

 deriniuin pyriforinc) which in another stage attacks several 

 commercially valuable species of pine. In the Wtsi the species 

 most subject to attack are Pinus coiitorfa, P. ponderosa and 

 P. divaricata, while in the East, Pinus pungcns and P. rigida 

 are victims. It is said that the rust is entireh^ dependent upon 

 the toad-flax for the completion of its life cycle, and if this be 

 so, the destruction of this plant in the vicinity of pine forests 

 and nurseries of young plants is to be desired. 



Fruits Eatex by Thrushes. — A Government report on 

 the food habits of our thrushes throws an interesting light on 

 one phase of seed distribution. Plants which produce fleshy 

 fruits such as berries are supposed to be disseminated by birds, 

 but wonder is often expressed at the unpalatable or CA'en 

 poisonous nature of many of these since it should cause them 



