186 STUDIKS IN INDIAN FIBRE PLANTS. 



burst, the filaments of the subulate set will then be found consider- 

 ably longer than those of the round set, and the stigma will then be 

 about the same height ; these long anthers come to maturity long 

 before the round ones, and about the time the stigma is among 

 them; but the style continues to grow longer, by which 

 means the bearded stigma pushes on with it much of the pollen 

 from the long anthers whose filaments do not lengthen any more : 

 but those of the round ones now begin to lengthen, pushing their 

 anthers considerably beyond the apices of the linear set, and even 

 with the stigma ; by this economy they come in contact with it be- 

 fore or about the time of their maturity. These changes I have 

 found most conspicuous in Crotalaria juncea and 'pentaphylla, whose 

 flowers are very large, every part being easily seen with the naked 

 eye. 



The fact that the subulate stamens shed their pollen in the 

 bud all round the style and stigma combined with the closely shut 

 and twisted keel would appear to greatly favour self-pollination in 

 this species and to render natural crossing rare. If this supposi- 

 tion is borne out by further observation on the behaviour of the 

 produce of pure lines of both varieties grown next to next and 

 natural crossing is found to be exceedingly rare, then it is likely 

 that few types of this species will be found in cultivation. 

 The absence of crossing would also explain the remarkable purity 

 observed in the crop as grown in the Central Provinces. No evid- 

 ence of natural crossing was observed in the pure lines of both 

 varieties grown at Piisa in 1909. 



The two varieties have been compared at Piisa for green 

 manuring purposes. The rapid germination and growth of the 

 Jubbulpore Sann are great advantages over the local variety in 

 years of short rainfall, or when it is essential to estabhsh the crop on 

 the early pre-monsoon showers. This rapid growth also prevents 

 the early growth of weeds. At a much later period of growth and 

 after the green manuring stage these advantages to a great extent 

 disappear and are even reversed. The branching of the local 

 variety before flowering time forms a dense canopy under which 

 weeds are killed out, while the more erect habit of the Jubbulpore 



