83 



THE EEMALE FLOWER FROM PRIMORDIUM. TO SEED. 



On the endogenously arising inflorescences of Rhopalocnemis, 

 thick scaly organs are formed, whose morphological value is 

 not quite clear. The axis of the inflorescence consists of a 

 parenchyma in which a number of vascular bundles are immersed. 

 These vascular bundles are rather irregularly distributed but 

 usually some of them are arranged in a ring (fig. 48 PI. X). 

 I have never seen a cambium develop from this ring so that 

 thickning growth must take place by means of divisions in 

 the parenchyma. The parenchyma of the axis is larger celled 

 in the center than towards the periphery and shows itself to 

 be covered by an epidermis (fig. 9 PI. IV). If one removes the 

 scales of such a young inflorescence, as yet immersed in the 

 tissue of the tuber, and looks at the surface of the inflorescential 

 axis one sees a perfectly smooth surface which shows neither 

 hairs nor flowers. Only rather large pits are seen at the places 

 where the stalks of the scales have been l^roken off. Soon the 

 first traces of flowers are seen as very small warts (fig. 10 

 PI. IV) which at the very beginning are formed by a division of 

 the epidermis alone (fig. 11 PI. IV), while very soon the sub- 

 epidermal layer begins to take part in it also (fig. 12 PI. IV). 

 We remark simultaneously (comp. fig. 10 with fig. 9 PI. IV) 

 that the scales have formed a clearly differentiated stalk, and 

 have been widened considerable in those parts which are nearest 

 to the axis of the inflorescence. At the same time the scales- 

 stalks have grown somewhat, bringing the bases of the scales 

 at a small distance from the axis of the inflorescence , thus 

 making room for the flowers in development. The enlargement 

 of the basal part of the scales causes the latter to stick closely 

 together thus protecting the young flowers against unfavorable 

 external influences. In the mean time the inflorescence has 

 pierced the overlaying cellsheathes of the tuber and has become 

 visible ; at this moment we flnd the surface of the inflorescential 

 axis to be covered by a dense filt consisting of chaffy hairs. 



