DIMORPHIC BRANCHES OF THE COTTON PLANT. 23 



An apparent transformation of the axillary leaf bud into a flower 

 bud is of frequent occurrence in some of the cluster varieties of 

 Upland cotton, but is also common in Egyptian cotton, especially in 

 the Dale variety that has the abnormal branches and bracts. 



A transformation of leaf buds into fruiting buds might be expected 

 to increase the fertility of the plants, but this is not the result in the 

 Egyptian cotton for the reason that the most frequent effect of this 

 transformation is to put an end to the growth of a fertile branch. 

 A ffrowine branch must have a leaf bud at the end, and if this ter- 

 minal bud is transformed into a flower, the branch does not continue. 

 If the transformation is successfully accomplished, we secure one 

 additional boll, but at the expense of a fertile branch which might 

 produce several bolls. The loss is still further increased by the fact 

 that the plants addicted to this habit of transforming leaf buds into 

 flower buds lose a very large proportion of their buds by abortion. 



The frequency of abnormalities in the bracts and in the floral 

 organs shows a general disturbance of the normal process of heredity 

 in the newly imported varieties, such as frequently attends hybridiza- 

 tion. In the Egyptian cotton varieties it does not appear that these 

 phenomena are directly connected with hybridization, for they occur 

 in large numbers of plants that give no evidence of admixture of 

 Hindi or Upland characteristics. Nevertheless, the whole series of 

 abnormalities may be considered from the standpoint of hybridiza- 

 tion, in that they represent intermediate stages between organs of 

 the plants that are normally distinct and different from each other. 

 In each case there is a failure to follow the normal paths of develop- 

 ment by which the normal individual advances from the characters 

 of the seedling to those of the adult plant. Although a plant may 

 have all of its characters normally developed in some of its parts, 

 the parts that show the intermediate conditions of the characters may 

 be quite as abnormal as in any hybrid, and resulting sterility is quite 

 the same from the practical standpoint. 



The study of the evolution of plant structures has led to the recog- 

 nition of a phenomenon called translocation of characters, or homoeosis, 

 the carrying over into one part of the plant of a character that nor- 

 mally appears in another part, such as the manifestation of the bract 

 characters by the next leaf below the bracts in Dale cotton." 



<»Leavitt, R. G. A Vegetative Mutant and the Principle of Homoeosis in 

 Plants, Botanical Gazette, Januaiy, 1909, p. 04. 



" In lionuieosis a character or a system of organ ization which has heen evolved 

 in one part of the body is transferred ready-made to another part. The great 

 mass of instances ai'e of the class called teratological. By this designation we 

 mean substantially that they are suddenly appearing deviations from the cus- 

 tomary structures." 

 198 



