catonus. 



SEED-COLORATION 397 



out, so that the coats have the sodden, wrinkled appearance of 

 a washerwoman's fingers. 



With Abrus precatorius, as with Canavalia gladiata^ the Abruspre- 

 characters of the resting seed are all acquired in the closed 

 pod. Here again the pink colour of the soft immature seed 

 in the green pod gives place to a scarlet red in the hard 

 matured seed of a pod about to open ; and here also, when 

 the seed swells for germination, it resumes the original pink 

 hue of immaturity. With both these plants there is but little 

 difference either in colour, size, or consistence between an 

 immature seed taken from a green pod and a resting seed that 

 has swollen for germination. That this change from red to 

 pink in the germinating seed is due to the hydration of the 

 coverings is indicated by the behaviour of the seed when 

 allowed to soak in water after being filed. The colouring 

 matter dissolves out and the red seed becomes almost blanched. 



In the case also of the seeds of Adenanthera pavonina all 

 the colour-changes take place in the closed pod. As observed 

 for me by Mrs H. B. Warde in Jamaica, the soft immature 

 seeds in the green pod are first green and then yellow ; and as 

 the pod begins to brown and dry the seeds turn pink, and 

 when the shrinking and hardening processes approach comple- 

 tion the permanent bright red hue is assumed. It is not 

 necessary for the development of the last two stages in the 

 coloration that the pod should remain connected with the 

 plant. If the green pods are allowed to dry after picking, 

 bright red seeds will be found in closed pods after a few weeks. 

 Though I had not the opportunity of observing the actual 

 stages in coloration on the tree, specimens of all of them were 

 kept for me. When the seeds are absorbing water and swell- 

 ing for germination, they do not, as with those of Abrus 

 precatorius and Canavalia gladiata^ regain the pink hue of 

 immaturity. The outer red skin is thrown oflF by the swelling 

 of the under layer, and the seed assumes the yellowish colour 

 of the second stage of coloration in the green pod, a stage 

 earlier in immaturity. 



