104 AMERICAN JOURNAL OF BOTANY [Vol. 10, 



will be considered later.) Hori regards flowering in bamboos as a result of 

 an increase in sugar content of the sap due to the inability of the plant to 

 attain the necessary salts for nourishment owing to the dryness of the soil. 

 While Dr. Hori's interesting observations (of which he has kindly given me 

 a resume) tend to support his theory, they cannot be regarded as generally 

 applicable, since, as we have seen, bamboos flower even though profusely 

 watered, and also fail to flower though subjected to repeated seasons 

 of drought. 



Macmillan (16) is also of the opinion that a depletion of nourishment is 

 the cause of flowering in some bamboos. He states (p. 125): 



It would thus seem as if the exhaustion of nutriment rather than an infectious influence 

 were responsible for the more or less simultaneous flowering of the Giant Bamboo. The 

 vigorous growth of the plant is such that it cannot go on growing and extending indefinitely. 

 The enormous demands it makes on the soil can be realized by any one who has seen the 

 "ruins" of an old clump, the huge crevices and upheavals formed by the elevated stumps 

 as if the result of an earthquake. 



Macmillan's description of the elevated base of an old bamboo clump is 

 very graphic. But on such a mound of stumps measuring fully eight feet 

 in diameter and three feet in height I have seen healthy culms growing as 

 luxuriantly as those of any bamboo clump in the Buitenzorg Gardens. 



Macmillan reports the continuation of the vegetative growth of two 

 clumps of Dendro calamus giganteus as a result of increased nourishment. 

 It seems that two of the flowering clumps at Peradeniya, having regained 

 a more vigorous condition, "gave up blossoming entirely, presumably 

 because their circumference had struck richer soil" (16, p. 125). 



This instance at Peradeniya is especially interesting because the bamboo 

 in question happens to be of the same species as a young plant recently 

 growing in the Buitenzorg Gardens, which was transplanted from an old 

 clump and thus given an opportunity to regain a more vigorous condition 

 by striking new soil. But it refused the opportunity and soon followed in 

 the path of the parent plant. 



There had been growing for many years in the Buitenzorg Gardens a 

 magnificent clump of Dendro calamus giganteus remembered for its size and 

 beauty by all the older workers of the's Lands Plantentuin. In 19 18 this 

 entire clump of bamboos flowered and died. Not wishing to lose the last 

 specimen of so fine a bamboo (seeds are not produced), the director of the 

 gardens had a few culms, which were still in healthy condition, removed 

 from the parent clump as soon as the latter commenced to flower. It was 

 hoped that these transplanted culms would continue their vegetative 

 growth without flowering. Such was not the case, however. One of the 

 transplanted clumps soon flowered and died. The second clump lived 

 scarcely more than a year after transplanting, when it too flowered and died. 

 I saw this small plant when the long pendent blooms were still hanging to 

 the then nearly dead culms (fig. 4). New and richer soil did not cause this 



