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opportunity to prove to the world that it is not necessary to 

 lose a crop of such importance as linseed from among your rota- 

 tions, nor is it necessary that your wheat yields should fall from 

 the now promising ones of thirty to sixty bushels per acre to 

 the general average of twelve to fifteen." 



The May Bulletin of the Torrey Botanical Club contains an article 

 by Harry B. Brown on the genus Crataegus, with some theories 

 concerning the origin of its species. Prior to 1896 about one 

 hundred North American species of Crataegus had been described ; 

 since then eight hundred and sixty-six species and eighteen varie- 

 ties have been described. Three explanations might be given: 

 that the early systematists were not careful workers; that the 

 number of species has multiplied greatly recently ; that the older 

 species are hybridizing. Opinions from leading systematists are 

 given. Mr. Brown thinks that the present different concept of 

 species is responsible for part of the increase ; and the rest may be 

 accounted for by (i) the decrease in forested land and the con- 

 sequent increase in the number of Crataegus plants now occupying 

 the space and (2) by the fact that many of the present forms seem 

 to be hybrids. 



In the Plant World for July an unusual formation of adventi- 

 tious roots is described by F. A. Wolf. "During a storm the 

 trunk of this large hackberry tree had been split and the fallen 

 portion was subsequently removed. At a point about eight feet 

 above the ground and a little above the broken edge of the tree 

 a cluster of fibrous roots were formed. Some of these grew to be 

 over a foot in length and larger in diameter than a lead pencil." 

 Mr. Wolf says that there "is no doubt that no such phenomena 

 would be expected to occur in a normal healthy tree, yet this is 

 not an adequate explanation for their formation. Certain it is 

 that the vitality of the tree had been seriously impaired and it 

 responded to this abnormal condition by a peculiar development 

 of roots. It would seem, too, that such a growth might better 

 be expected in a more humid region and not under semi-arid 

 conditions such as prevail about Austin. This is one of the singu- 



