50 



JOURNAL OF THE ROYAL HORTICULTURAL SOCll<n'V. 



For centuries the seed i^rowcr lias relied on " roi^iieiii,'^' " io ensure ;i 

 true crop. The process oi' " rugueing " however, Ihimgh Leuiporarily 



Fig. 31. — Cattleya Harrisoniana alba. {Garden.) (p. 45) 

 A pure C albino, 



effective, involves in many cases a serious annual expenditure of trained 

 and expensive labour, without permanently achieving its object. It 



