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Note on an Orderly Dissimilarity in Inheritance from Different 



Parts of a Plant. 

 By W. Bateson, F.R.S., and Caroline Pellew. 



(Received November 9, 1915.) 



In a recent paper* we described the genetic behaviour of the peculiar, 

 wild-looking, " rogue " peas which appear as the offspring of the cultivated 

 types. In several respects the phenomena are as yet without parallel. 

 The genetic constitution of the F x plants raised by crossing types with rogues 

 was especially remarkable. These plants, as young seedlings, are intermediate 

 between types and rogues, but, with rare exceptions, as they mature they 

 become normal rogues and behave genetically exactly like pure-bred rogues, 

 producing only rogues as offspring. We conjectured that a segregation of 

 factors takes place in the soma, such that the type elements are left behind 

 in the base of the Fi plant and are thus excluded from the germ lineage. 



Tbe observations here described, though very imperfect, are entirely 

 consistent with the facts related above and with the interpretation offered. 

 As a season must elapse before the evidence can be materially increased, we 

 venture to make this preliminary record. 



In the paper referred to we described certain intermediate forms found in 

 Sutton's " Early Giant " (a strain of Gradus). The offspring of these plants 

 shows them to be commonly of two classes : those which throw predominantly 

 rogues and some types, and those which throw predominantly types and a 

 few rogues. The characters of such intermediate plants often change pro- 

 gressively with growth in the direction of the rogue form, the lower parts 

 being more type-like, the upper parts more rogue -like. This fact, taken 

 together with the observation that it is only the lowest leaves of the Fi plants 

 which show any influence of the type-parent, suggested that when the 

 offspring consists of a mixture of types and rogues, the types may be derived 

 from the lower pods and the rogues from the upper pods. To test this 

 possibility we this year saved the upper and lower pods separately from 

 many plants. The bulk will be sown next spring, but, though the results of 

 autumn sowing are unsatisfactory inasmuch as the plants cannot reach 

 maturity, we have made a preliminary trial with a small quantity of seed. 

 Three families came up which contain the requisite mixture of forms. 

 Several plants were unfortunately damaged by Noctuid larvse and had to be 

 reckoned as doubtful, but the general result of the experiment is quite clear. 

 * ' Jomn. Genetics,' vol. 5, p. 13 (1915). 



