CHAPTER VI 



ADDITIONAL EVIDENCE ON THE CONTRAST IN BEHAVIOUR 

 BETWEEN PERMEABLE AND IMPERMEABLE SEEDS 



Additional 

 experiments 

 by punctur- 

 ing or filing 

 impermeable 

 seeds. 



This chapter contains the bulk of the data on which are based 

 the distinctions in behaviour between impermeable and 

 permeable seeds as typified by those of Guilanaina bonducella 

 and Canavalia ensiformis in Chapter IV. Some of their 

 differences, such as those concerned with hygroscopicity and 

 permeability, will be found generally treated in the preced- 

 ing and in following chapters. Here we are at first more 

 especially concerned with the distinctions in their behaviour 

 when bared or punctured or broken up and exposed to the air. 

 We will take first the additional evidence concerning the 

 effects of puncturing or baring the three types of seeds 

 described in the preceding chapter — the impermeable, the 

 variable, and the permeable — ^and will commence with some 

 additional results of experiments on punctured impermeable 

 seeds. The effect of increasing the weight through the 

 absorption of water from the air has already been discussed in 

 the case of Guilandina bonducella in Chapter IV. The results 

 for the seeds of Entada scandens in an experiment covering two 

 years are tabulated below. 



[Table 



114 



