SEED-NUMBER AND FRUIT-SIZE 337 



usually one or two large seeds in each pod, there is a decided 

 repetition of the behaviour of capsules in these respects, thus 

 supporting the conclusion derived from the legumes of Leucana 

 glauca and Alhizzia Lebbek that it is the pod with few seeds 

 that is most likely to follow the principle of the capsule. 



But even in such a case this seems only to apply to legumes 

 with a few large seeds. More often it would be difficult in 

 small pods containing only a few seeds to discover any such 

 relation. Thus there is certainly but little to be made out of 

 the results for Abrus precatorius given in the following table, 

 in the columns of which data for larger legumes, like those 

 of Canavalia obtusifolia^ will be found, which are equally 

 indeterminate in their indications. Doubtless the scantiness 

 of the materials is partly responsible for this ; but we might 

 have looked for some more consistent results than are given 

 for dry legumes in the subjoined table. There are evidently 

 some disturbing influences at work that cause this irregularity 

 in the relations between fruit and seed in these legumes. 

 These influences, as will subsequently be shown, are connected 

 with the failure of seeds and the abortion of ovules. 



One disturbing cause is needlessly brought into action 

 when we employ indiscriminately legumes that have dried on 

 the plant and those that have dried in an experiment. A 

 serious eflfect may be thus produced, a matter discussed in 

 Note 16 of the Appendix. This influence has, however, been 

 avoided in my own results by using for each plant only fruits 

 dried in the same way. 



Coming to the evidence of dried capsules, like those of 



Iris Pseudacorus and Iris fix tidissima^ we find the features of the 



moist capsule reproduced in the following table. As the 



fruit increases in size and weight and in the number of its 



seeds, the proportion of the pericarp steadily decreases, but, 



unlike the moist fruits, there is an increase in the weight of 



the individual seed. Other types of capsules, such as those 



illustrated by the siliquiform fruits of Moringa pterygosperma^ 



seem to follow the same rule. 



22 



