452 



A NATURALIST IN THE PACIFIC 



CHAP. 



By referring to the table below it will be observed that there is 

 no period of rest in the growth of the fruit up to the date of the 

 protrusion of the radicle. It will now be shown that there is 

 normally no pause between the epoch of the maturation of the 

 seed and the beginning of germination, or, in other words, that 

 from the time of the fertilisation of the ovule to the onset of 

 germination there is no cessation in the process of growth of the 

 embryo. That period of dormant vitality which almost all seeds 

 pass through forms no normal feature in the life-history of this 

 species of Rhizophora. 



Rhizophora mangle and R. mucronata. 



Rhizophora mangle. 



Growth of fruit in height. 



Lines or tenths of 



an inch (millimetres 



in brackets). 



2(5) 



3(7-5) 



4 (io) 



5(12-5) 



5d5) 



7d75) 



8(20) 



9(22-5) 

 10(25) 

 11 (28) 



Number of days 



since 



fertilisation. 



SO 



42 



50 



61 

 67 

 74 



83 



92 



100 



105 



I Protrusion 

 of the 

 hypocotyl 



Growth of the protruding hypocotyl. 



IO (25) 

 20 (50-5) 

 30 (761 

 40 (101-5) 

 50(127) 

 60 (152) 



7o(l77-5) 

 80 (203) 

 90 (228) 



127 

 141 



151 

 160 



167 

 175 

 185 

 202 

 222 



229 



( 



Fall of the 

 seedling 



Explanation of the Table. 



We have here shown the period 

 between fertilisation and the fall 

 of the seedling from the tree. 



This period divides itself into 

 two parts, the first being con- 

 cerned with the continuous growth 

 of the fruit and of the inclosed 

 embryo until the tip of the hypo- 

 cotyl appears through the apex of 

 the fruit, the second being in- 

 dicated by the growth of the pro- 

 truding hypocotyl until the fall 

 of the seedling. 



The height of the fruit is mea- 

 sured from the base of the calyx- 

 lobes, and the length of the hypo- 

 cotyl at first from the apex of 

 the fruit and afterwards from the 

 edge of the protruding neck of the 

 cotyledonary body. The height 

 of the ovary at the time of fertilis- 

 ation is about 3 millimetres ; and 

 from that time onward it is to be 

 regarded as a fruit. 



