Feb., 1923] 
SEIFRIZ — CAUSES OF GREGARIOUS FLOWERING 
99 
at all times of the year. Some few arid localities occur, but they are small 
and infrequent above 4000 feet. Relatively dry weather may come occa¬ 
sionally at high.altitudes, but never a drought above 5000 feet, the elevation 
at which Chusquea grows. Chusquea abietifolia flowered gregariously in 
the mountains of Jamaica in 1918 (20). Over an area ten miles in length 
(investigated by the writer) the trails were, in 1919, lined with dead tangled 
masses of this climbing bamboo. The two years immediately preceding 
the flowering of Chusquea were (at Cinchona) unusually moist ones. It is 
interesting to note that specimens of Chusquea abietifolia sent to Kew, 
England, in 1884, a year prior to the last previous flowering of the plants 
(in 1885, the life cycle of Chusquea being thirty-three years), flowered 
simultaneously with the plants in Jamaica. 
The behavior of Chusquea in Jamaica stands in further opposition to 
the belief that lack of moisture may cause flowering in bamboos in that it 
does not support the statement of Brandis that “there are indications, that 
in dry stony places . . . bamboos flower earlier and more abundantly” 
(1, p. 662). It was in just such places that the only green living specimens 
of Chusquea abietifolia were found in the mountains of Jamaica. On an 
exposed hot and dry spur, sparsely covered by a typically xerophytic 
vegetation, were growing a quantity of old, green, and thriving specimens 
of the climbing bamboo. Immediately below this dry spur on which living 
old plants of Chusquea were growing, there is a moist, cool ravine. Here no 
adult living specimens were found, but there existed instead the condition 
prevailing generally throughout the mountains: old plants were dead and 
growing seedlings were abundant. The old living specimens on the arid 
spur above were not in fruit. Flowering had not taken place earlier, as 
Brandis suggests, but, on the contrary, had been delayed. Possibly the 
climbing bamboo had in this more arid region assumed an altered life cycle. 
In comparing the behavior of the bamboos at Buitenzorg, Java, where 
droughts are unknown and dry seasons are infrequent, with the behavior of 
the bamboos in India and Ceylon, where dry seasons of several months 
come annually and droughts occur frequently, it will be well to consider 
with the bamboos the equally instructive case of the talipot palm, Corypha 
umbraculifera , which, like some bamboos, has a long vegetative period at 
the expiration of which the palm flowers and dies. Ordinarily Corypha 
umbraculifera does not flower gregariously nor at a fixed age, as do certain 
bamboos. Consequently, when many specimens of the talipot palm do 
flower simultaneously, one is likely to suspect the presence of some external 
factor which has aroused the palms to sexual activity. 
The most remarkable case of simultaneous flowering of plants of which 
I know is that which recently occurred at Peradeniya, Ceylon. In the 
annual report for 1918 of the Director of the Royal Botanic Gardens at 
Peradeniya (4) there appear the following three notes: 
Seven out of the sixteen talipot palms (Corypha umbraculifera) forming the avenue, 
