IOO AMERICAN JOURNAL OF BOTANY [Vol. 10, 



started by seed sown in situ in 1881, commenced to flower in June, and continued in blossom 

 until the end of the year, being at their best in October-November [PI. XII, fig. 1]. 



Bauhinia anguina, a very large woody climber with peculiar alternately compressed 

 chain-like stems, has this year fruited for the first time on record at Peradeniya. Trimen, 

 in his Flora, states: "Very rare, flowers and fruit not seen." 



The flowering of the giant bamboo (Dendrocalamus giganteus) is not now the rare 

 event in Ceylon it used to be. Nine clumps produced flowering stems during the early 

 dry months of the year. . . . None of these clumps have died. Eleven clumps of the 

 "male bamboo" {Dendrocalamus strictus) also flowered profusely early in the year. Of 

 these, five clumps have died in consequence. 



To this is to be added the interesting fact that at the same time that 

 the talipot palms were blossoming in the Gardens there were counted from 

 one observation point elsewhere in Ceylon two hundred talipots in flower. 

 So extraordinary a concurrence of the profuse flowering of four species of 

 plants, all of whose life cycles are very long — in the case of the two bamboos 

 about thirty-two years, of the talipot palm nearly forty years, and of the 

 liane Bauhinia so long that there is no record of it — is indeed an event that 

 forces one to search for some possible environmental factor which might 

 be responsible. 



The annual dry season of 1918 was in Ceylon longer than usual, suffi- 

 ciently long to be locally termed a drought. The remarkable flowering of 

 so many talipot palms throughout Ceylon and the simultaneous'flowering 

 of three other species of plants of long sexual periodicity was attributed to 

 this drought. 



Three objections can be raised against such a deduction. First, the 

 drought of 1918 was a relatively mild one. The total precipitation for the 

 four months (January to April) of the dry season was, to be sure, below the 

 average for this time of year (12.9 inches in 191 8 as compared with a normal 

 of 17.05 inches for these four months, all averages being based on twenty 

 years' records from 1901 to 1920) ; yet the difference is not very great. 

 Furthermore, if we review the records of the years immediately preceding, 

 we see that the dry season of the second year before the flowering of the 

 talipots and bamboos in the Gardens was also below the average; not 

 quite so low for the four months of the dry season as in 1918, but much 

 lower for January, when but 1.0 inch of rain fell (in 1916) as compared with 

 5.23 inches in 1918. And in February, 1916, there was but 0.03 inch of 

 precipitation. One would expect these two very dry months of 1916 to 

 have a more telling effect on plant life than the dry season of 1918. If we 

 go further back we find that there was a drought in 1903, and again in 1905, 

 of much greater severity than that of 1918, especially the latter one (1905) 

 when the total rainfall for the four months January to April was the lowest 

 on record for twenty years (1901 to 1920), namely, 4.9 inches or nearly 

 one third that of 1918. In 191 1 there occurred at Peradeniya a drought 

 which, because of its duration, was more severe than any so far mentioned. 

 In this year there fell during the. five months of January to May but 12.78 



