624 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



find no record since it was first described in " Grevillea " about twenty- 

 three or twenty-four years ago. Samples ol bulbs had also been 

 submitted by Mr. Jan de Graaf to the Phytopathological Institute, 

 Amsterdam, and they reported them to be attacked by Fusarium 

 hulbigenum, adding that this fungus only thrives when the temperature 

 gets above a certain degree, and also when there is a certain moisture. 

 Mr. de Graaf states that bulbs kept spread out absolutely dry from 

 the moment they were lifted did not suffer. The writer, however, 

 refers to a case where a small stock of bulbs, stored where crowding 

 was improbable, had been affected. — H. R. D. 



Daikon (Japanese Radish). By E. de Noter {Le Jard. xxv. 576, 

 p. 54; Feb. 20, 1911). — Eight varieties of this Japanese vegetable are 

 recommended. They are much appreciated in their native country, 

 and contain a high proportion of nitrogen. They are used like turnips, 

 but have more flavour. They prefer a sandy soil with plenty of 

 manure dug in, and are best taken up when the frost has cut the leaves. 

 The slow-growing varieties must be sown April-May, and require four 

 to five months for development; the faster sorts should be sown in 

 the last two weeks of July, in rows 70-80 cm. apart; the seeds should 

 be 25-30 cm. apart, and should be thinned out as soon as the plants 

 are tall enough. They make vigorous foliage and never require 

 watering, beyond that provided naturally by rain. Animals feed 

 greedily on daikons. The crop can be stored in November and Decem- 

 ber in a cellar or silo, keeps till March, and is equivalent in its 

 nutritive properties to the potato. — F. A. W\ 



Dimorphic branches in Tropical Crop Plants. By 0. F. Cook 

 {U.S. A, Dep. Agr., Bur. PL hid., Bull. No. 198, Jan. 1911; plates). 

 — It is here pointed out that in five plants of tropical America — 

 Cotton, Coffee, Cacao, the Central American Eubber Tree, and the 

 Banana — definite dimorphism of the branches exists and has not 

 hitherto been sufficiently taken into account, either in breeding new 

 varieties or in the ordinary operations of cultivation and pruning. In 

 each of the five species of plants concerned there is a definite relation 

 between the function of the branches and their positions or places of 

 origin on the stem, but there is no general relation of position to func- 

 tion that applies to all these species or even to any two of them. It is 

 necessary to consider each plant separately in order to understand the 

 agricultural importance of the dimorphism of its branches. The subject 

 is here minutely considered ; the origin of the structural differences is 

 traced from the " metamers " or units of organic structure of which 

 each plant is made up; the position, the sequence, the point of depar- 

 ture, and the function of each type of branch is given for each species 

 of plant, and the various reasons which make the fact of their 

 differentiation important to cultivators is pointed out. 



In the case of the Cotton plant it has been noticed that one result 

 of the change of climate resulting, for instance, from importing plants 



