ABNORMAL "FLOWERS" OF HELENIUM AUTUMNALE, L. 951 



enclosed between the fused basal portions of the two carpels — has been 

 described above. 



All such cases of proliferation of the florets into shoots represent the 

 extreme form in which the tendency to vegetative, as opposed to the 

 tendency towards the more usual generative development, sets in. 



Passing outwards from the centre to the periphery, we find in certain 

 heads, but not in all, that forms standing midway between the tubular 

 disc- and the ligulate ray-florets occur ; and occasionally more or less 



T0l*$ CO 



Fig. 217. — Capitulum showing extreme Case of Proliferation of Ray- 

 florets ; also the Trumpet-shaped Character of the Ray-florets of 

 the Secondary Heads. 



trumpet-shaped ray-florets resembling in shape those of Centaurea may 

 be seen ; in such cases typically shaped ray-florets are, as a rule, absent. 

 Such transitional structures are very interesting as showing that the two 

 types of florets are essentially identical in structure. These semi-ligulate, 

 semi-tubular florets are usually of a yellowish-green colour (fig. 210, k ; 

 fig. 217. It was interesting to note that in a few heads yellow tubular 

 florets, of much greater size than those normally occurring in the disc, 

 were observed to be situated outside the ligulate florets of the ray. 



