36 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



flowers, and disarticulate. Often a bud is not killed outright, 

 but the outside members alone are injured. This is frequently 

 to be observed in Phalanopsis Schilleriana, where the petals 

 and column have not been reached by the poison. In due time 

 such buds expand, the sepals remaining dwarfed and in part 

 uninjured, whilst the inner parts develop normally. I have 

 noticed the same occurrence in Lcelia and in a few other genera 

 of Orchids. Very young buds are not so liable to injury as those 

 further advanced ; whilst flowers and flower-buds of the same 

 plant arc by no means always similarly affected. Thus in Salvia 

 lantanifolia, whilst buds disarticulate, expanded flowers are 

 uninjured; in Ixora (various species) the buds easily succumb, 

 though the flowers are unaffected. Then in Rhododendron 

 jasminiflorum the flowers are uninjured so long as the inflores- 

 cence remains wrapped in its bud-scales. The expanded flowers 

 also are little affected. But if the buds attempt to open during 

 fog they are almost invariably u caught." The buds push aside 

 or raise the bud- scales, but rarely succeed in freeing themselves 

 from them. It is common to find in a Ehododendron-house 

 scores of inflorescences trapped in this way in their scales. 

 The un expanded corollas then shortly disarticulate at the point 

 •of their insertion on the floral receptacle. But this happens 

 equally even if the buds be disembarrassed of their scales. 

 The moment of expansion seems, in this group, to be a very 

 •critical one. Possibly this is associated with the fact that the 

 exposure is, in the Rhododendron, very sudden. The buds 

 certainly are exceedingly sensitive to toxic influences at this 

 time. I have already stated that these inflorescences expand 

 readily enough in darkness. 



In Angrcecum sesquipedale the bright green buds turn yellow 

 and disarticulate. By comparing the action of fogs of varying 

 intensity I have found that the lateral buds are more sensitive 

 than the terminal ones. The former sometimes drop whilst the 

 latter remain and open later. The terminal bud I conceive to 

 be more favourably situated in respect of nutrition, and to be 

 thus slightly more resistant to poisonous environment, than the 

 laterals. But, of course, h is only fogs which are not the severest 

 that demonstrate this physiological differentiation amongst the 

 buds. 



Finally, many flowers do not show actual injuries. Limiting 



