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Some Variations in Plants. 



By F. M. Andrews. 



Ill the prof-eedings ol' the Indiana Academy of Science for 1905 and 

 ]IK)9 I have mentioned some variations in i)lant.s. Some of those have 

 heen noted and studied by de Vries, who considered the subject of such 

 importance as to undertalce its further study. 



Flattened stems of various liinds are not infrequently found and 

 sometimes twisted stems also. The latter de Vries'^ has noted in wild 

 teasels and he was able by selection and cultivation to increase the per- 

 centage of plants of teasel having this peculiarity. 



One instance of stem flattening, not due to a traumatic effect, is that 

 of the blackberry. The stems of this plant are ordinarily more or less 

 rounded in transverse outline and it would be interesting to see if this 

 monstrosity conld be increased in any way in plants grown from them as 

 iu teasels. 



This same tendency to pi'oduce occasionally flattened parts occurs in 

 dandelions. De Vries- was able to increase in various plants the per- 

 centage of flattened stems. Not infrequently the scapes of the dandelion 

 are so united with others and so flattened as to be more than a centimeter 

 in width. 



Likewise deviations are often shown in the flowers of dandelions 

 This is especially seen in the union of two or more heads of flowers. Two, 

 three and once five of flowers were more or less united into one and pro- 

 duced by this means a rather confused and irregular mass of many flow- 

 ers. Here also was a flattening of the more or less perfectly united scapes. 

 A sunflower which had several heads fused into one very large and curi- 

 ously vshaped mass was observed. 



The union, however, of most flowers or branches in the neighborhood 

 of one another are always of rare occurrence, as DeVries^ has mentioned 

 is the case with most plants. An exception to this is seen in the case of 



' De Vries — Species and Varieties, their Origin by Mutation. 1905, pp. 404, 405. 

 = De Vries — Species and Varieties, their Origin by Mutation. 1905, p. 411. 

 =■ De Vries — Species and Varieties, tlieir Origin by Mutation. 1905, p. 428. 



