SEIFRIZ: THE TALIPOT PALM AT PERADENIYA, CEYLON 349 
appear to have been rhythmic. The so-called Briickner (1) 
cycle of 35 years is very irregular in length, and is, apparently, 
confused with volcanic explosions. This cycle too, if indeed 
there really is such a one, is of small amplitude. Climatic 
changes of the geologic past are certain, but they are of irregular 
occurrence and of unequal duration (3), and of much too great 
a length to be of any interest to us here. So far as the cause 
of gregarious flowering is concerned the meteorologist has nothing 
to offer which appears to have any bearing on the problem. 
Were we willing to accept the popular belief in the existence 
of climatic cycles,* we should still be confronted with the task 
of explaining why these cycles cause the talipot palm to flower 
in 34 years while certain. bamboos reach sexual maturity in 32 
years; and why the climatic cycle should cause Chusquea abieti- 
folia and Bambusa arundinacea to reproduce every 32 years 
while other bamboos flower most irregularly (this seems to be 
generally true of many of the Philippine species). 
The persistent attempt of some investigators to interpret 
rhythmic vital phenomenon in terms of environmental factors 
is apparently due, in part, to opposition to any hypothesis of 
behavior which dissociates the organism from its environment. 
But there is nothing mysterious in a rhythmic life cycle or an 
innate sexual periodicity. The rhythm in the flowering of talipot 
palms and bamboos is no more extraordinary than rhythmic 
sexual periods in animals, the rhythm of the life cycle of man, 
and the rhythmic beat of the heart. The causes are simply 
internal instead of external. 
Conclusion.—All available evidence points towards a heritable 
tendency as the cause of gregarious flowering in the talipot 
palm, Curypha umbraculifera. 
cknowledgment.—The photographs published as Plates 8 
and g are the work of Platé, Ltd., Ceylon, and are published 
* An interesting account of a popular belief in climatic cycles is the fol- 
lowing from Francis Bacon (4). ‘There is a toy, which I have heard, and 
I would not have it given over, but waited upon a little. They say it is ob- 
served in the Low Countries (I know not in what part), that every five and 
thirty years the same kind and suit of years and weathers come about again; 
as great frosts, great wet, great drought, warm winters, summers with little 
heat, and the like, and they call it the prime; it is a thing I do the rather 
mention, because, computing backwards, I have found some concurrence.” 
