38 Colour and other Characters in the Potato 



a close cone similar to that seen in the various true wild species, 

 and through the apex projects a short style ending in a simple knob. 

 The anther contains abundant pollen. 



The corolla is very definitely wheel-shaped, the tips of the petals 

 recurve ; they are rather sharp and hairy, and the calyx is hairy and its 

 five processes are long. 



The tubers are borne on rather long stolons. They are white and 

 round, but the shape (Plate XXVII) is not typical of "round" as 

 we have met it before in this paper. The tubers are irregular, neither 

 oval nor long, but are often depressed at various points, so that 

 although the general shape is round, the actual circumference is not 

 necessarily circulai-. 



The size is variable. When the tubers were first cultivated here 

 they were not more than \\ inches in diameter; in 1909 I had some 

 up to 3 inches in diameter. 



The taste is bitter. 



In 1906 Mr Sutton informed me that he had for over 20 years tried 

 to self and cross this variety and had failed. In that year, however, a 

 plant bore one berry. I, also, after repeated trials, in 1906 succeeded 

 in making a cross. In 1907 Mr Sutton again obtained selfed berries, 

 and some tubers I had sent to the North of Scotland set seed naturally 

 and crosses were made. Hence, after over 20 years of observed sterility, 

 this variety suddenly flowers out into fertility in Reading, Scotland 

 and North Herts, which, as we shall see, has cost it dear. The tubers 

 in both 1906 and 1907 showed no variation, except a slightly enlarged 

 size. In 1908 when the plant first set seed naturally in Barley, it was 

 noticed that the tubers of one plant had a slight violet tinge in the 

 skin in places ; this plant set seed in addition to one other, and 30 of 

 the seedlings came from this plant. There is no evidence that the 

 seedlings are, as a whole, different from those which did not show this 

 vegetative variation. 



The fertilization of the plants took place naturally, but at a date 

 when all the other potato plants in my garden had ceased flowering 

 and when some F^ " Congo " crosses, which were close by, had already 

 formed good-sized berries. 



Immunity to Disease. (Phi/tophthora infestans.) During the culture 

 of this variety in Reading it was noted for its immunity to disease. 

 In my garden it was in 



1906. Perfectly immune from disease in haulm and tubers. 

 Three hybrid seeds only obtained. 



