XXX BRUGUIERA 463 



rest on the following day. During the next day or two the petals 

 and the stamens fall out of the flower. In wet weather, the petals 

 never acquire elasticity, and in consequence do not unfold. In this 

 case pollenisation is never effected, and the folded petals soon fall 

 to the ground, carrying the stamens within them. Cross-fertilisation 

 would be much more likely to occur with species of Bruguiera (if, 

 as is probable, the same process of pollenisation is usually followed) 

 than with species of Rhizophora, since the stamens are securely 

 inclosed in the petals for some hours after the expansion of the 

 flower. 



Nearly eight weeks pass between the date of fertilisation and 

 the commencement of germination. This is somewhat similar to 

 the period given for Rhizophora mangle, namely, nine weeks, and it 

 obviously leaves little or no time for any stage of quiescence or 

 dormant vitality in the case of the seed. The changes which the 

 fruit undergoes in this interval are a considerable increase in girth 

 and a thickening of the calycine walls, together with a contraction 

 of the mouth of the tube. However, I found no method sufficiently 

 accurate for recording the rate of increase of the fruit. 



It is known that germination is in progress when the end of the 

 hypocotyl begins to lift up the lining membrane at the bottom of 

 the calycine tube (see Figs. 2 1 to 26). The floor of the tube begins 

 to bulge up, but since this cannot be well seen at first, a better 

 index is afforded in the elevation of the style which accompanies it. 

 The top of the style preserves previous to this time a constant level 

 with regard to the tips of the calycine teeth. But this does not 

 indicate the actual beginning of germination. As shown in Fig. 21, 

 the seed lies about two and a half lines (6 mm.) below the floor of 

 the calycine tube, and the tip of the hypocotyl has to penetrate the 

 intervening tissues before it can push up the lining membrane and 

 raise the style. Judging from the subsequent rate of growth, 

 seven or eight days at least, and perhaps as much as two weeks, 

 are requisite for this purpose. It is not necessary to give further 

 details here, and it may be at once stated that the average of 

 numerous observations on the length of the interval between 

 fertilisation and the elevation of the style was sixty-four days, the 

 range being fifty-nine to sixty-nine. After deducting ten days for 

 the time occupied for the radicle in reaching the floor of the calycine 

 tube (see Figs. 22 and 23), we obtain, as already remarked, nearly 

 eight weeks as the time elapsing between fertilisation and germina- 

 tion. 



The radicle or hypocotyl, therefore, in the first stage of 



