THE ANGIOSPERMAE 



1579 



endocarp. The former has oval-shaped windows exposing the endocarp 

 over each seed and a cap of the endocarp is pushed off by the radicle. In 

 this fruit, as in some others, the number of seedlings obliged to germinate 



Fig. 1439. — Nipa fruticans. A, Germinating fruit. B, The same in section. 

 (c = cotyledon. h = haustorial radicle.) (After Veleiwvsky.) 



close together results in severe competition, so that only one usually sur- 

 vives. The extreme case of this germinal competition is that of BerthoUetia 

 excelsa, the Brazil nut, in which a hard fruit like a small cannon-ball holds 

 a number of seeds. The only opening is at the base, which is covered and 

 closed by the woody calyx. The seeds germinate in the fruit and there is a 

 keen struggle for survival, as only one can successfully occupy the "escape 

 hatch " and establish itself outside. Such methods look wasteful but they 

 may have an evolutionary value. 



