INTERRELATIONS BETWEEN PARTS OF PLANTS 407 



the stock and scion, however, and then they will develop into 

 shoots of a combined nature. These will be chimeras, in which 

 one-half of the tissues will belong to one plant, the other half to 

 the other. And if, for instance, the boundary line passes across 

 a leaf, the latter will be of an asymmetrical form (Fig. 127, 2). 

 Such chimeras are called ''anticlinal." 



Winkler has obtained chimeras of a still more peculiar nature. 

 Sometimes the buds are so formed that the outward layers of 

 the growing points belong to one plant and the inner tissues to 

 the other. As a result, all the organs developing from these 

 buds consist of two kinds of tissues, the external tissues of one 

 kind and the internal of another. According to their external 

 appearance, such chimeras, called ''periclinal," show an inter- 

 mediate character between the two species [Fig. 127 (3)], but 

 cytological investigations have shown that the tissues of each 

 component preserve the number of chromosomes characteristic 

 of it, as well as other pecuharities. Hence, even in this close 

 union, the reciprocal effect of the two species that are closely 

 joined by growth is not very great. 



Other types of chimeras have been obtained, and it has been 

 estabhshed that some varieties that have been reproduced vege- 

 tatively for a long time, e.g., Cytisus Adami, many varieties of 

 Pelargonium, some clones of potato, etc., are chimeras with their 

 inner tissues belonging to one plant and the exterior to another. 

 While the fruits of such chimeras are usually of a mixed nature, 

 the seeds always belong to the plant that forms the inner 

 tissues. Chimeras can be preserved only by means of vegetative 

 propagation. 



General References 



Argles, G. K. a review of the literature on stock-scion incompatibility in 

 fruit trees, with particular reference to- pome and stone fruits. Imp. 

 Bur. Fruit Prod. Tech. Communication 9, 1937. 



Child, C. Certain aspects of the problem of physiological correlation. 

 Am. Jour. Botany, 8: 288-295, 1921. 



Clark, W. G. Electrical polarity and auxin transport. Plant Physiol., 



12 : 409-440, 1937. , , 



Gardner, V. R., F. C. Bradford, and H. D. Hooker. -Fundamentals of 



Fruit Production," Sec. VI, McGraw-Hill Book Company, Inc., New 



York. 1922. u r. o o k 



GoEBEL, K. -Organography of Plants," Sec. V. Trans, by C. B. Balfour. 



The Clarendon Press, Oxford. 1900. 



