II. CROPS WITH CLOSED FLOWERS. 

 1. Wheat. 



In general, the flowers of all the species and varieties of wheat 

 are self-fertilized, pollination taking place before the extrusion 

 of the anthers. Instances of undoubted natural crossing are 

 rare in regions such as Northern Europe,' and some observers 

 even state that it does not take place.' Three undoubted cases 

 have been recorded in England and these have been referred to in 

 a recent paper. ^ 



While natural crossing seems to be exceedingly rare in damp 

 climates, such as that of England, there is considerable evidence 

 that it is more frequent in drier and more sunny climates like those 

 of the continent of Europe and of North America. Cases of spon- 

 taneous crossing have been recorded by Le Couteur* in Jersey and 

 by Koernicke' at Popplesdorf, while Fruwirth,' in a recent 

 work, has brought together most of the recorded examples in the 

 case of the wheat crop. Kiessling,'' in Bavaria, has recently 

 described eight cases of natural crossing among German wheats, 

 and he considers that its occurrence is more frequent than 

 is generally believed. 



In a recent paper^ we' have discussed the occurrence of this 

 phenomenon in India. Four cases of natural crossing were 

 observed in the single ear cultures sown at Lyallpur in 1906, while a 



1 See DatwiD, Animals and Pltvitf nnder Doiiicdlcation, and Biffen, Journal of Agnctil. 

 tural Sr'u'iire, Vol. I, 1905, p. 9. 



2 SeeGartoD, Journal of the Farmers' Cluh, WOO, p. 47, and De VrieF, Spceh'K and 

 Varieties, their origin by Mutation, 1906, p. 98. 



8 Howard & Howard, Memoirs of the Department of Af/riculture in India (Botanical 

 Series), Vol. II, No. 7, 1909. 



♦ Le Couteur, The Varieties, Projyerties and Classification of Wheat, Jersey,' 1872, p. 132. 

 6 Koernicke, J)le A>'ten nnd Varietdten des Getreides, 1885, s. 31. 



« Yva\\\x\.\\,Die Zuchtung derlandioirtschaftlichen Knlturpjlanzcn, Bd. IV, 1907, s. 91, 

 T Kiessling, Fuhling's landwirtschaftliche Zeitung, Bd. 57, 1908, s. 737. 



