ANTHOCYAN IX THE PETALOID CALYX. 13 



lower side. A very quick and remarkable develoj)raeiit of red 

 aiitliocyaii on some injured ]mrts of the calyx-leaf is particularly 

 noticeable, and is most apparent on the uj^per greenish side. 

 (Fig. 1).). This phenomenon is in entire agreement with the 

 observations made by Linsbauer, Ludwig and Molisch. Now when 

 the red colour of the lower side attains its maximum, it appears 

 as a somewhat dark red, whilst on the veinal surface it is a 

 rather distinctly crimson red. This dark red colouration is chiefly 

 due to the mixing of the epidermal deep red, and the hypodermal 

 blue, anthocyan. (Fig. 10.). 



In the course of the process of the degeneration of the 

 calyx-leaf the interveinal mesophyll i)arts become dark brownish, 

 then gradually dry up with the decrease of the sap, and finally 

 die out. After the removal of the destroyed mesophyll parts 

 there still remains the brownish skeletal vein-net of the calyx- 

 leaf. This dead calyx-net is not deciduous till the spring of the 

 next year. 



Microscopical structure. — Both red and blue anthocvans now 

 l)ecome nuich more concentrated in all the cell-sap. Nevertheless, 

 the colouring matter is still to be found in some cases in its 

 various younger stages — colourless, yellowish and of a pale 

 red. In this phase it is wortli noticing that violet or bluish 

 crystals and refractive globules appear in the outer layers of the 

 calyx-leaf. (Fig. 12.). 



]\Iany of the violet crystals appear granular and measure 

 about 5 /^- on the average. Some of them have the form of a 

 needle shaped prism, 7-9 p- long. They are found in the hypo- 

 dermal or epidermal cells on both sides of the calyx-leaf. Their 

 chemical reactions completely agree with those of the blue or 

 violet cell-sap, and hence these crystals must be regarded as 



