IN CEYLON. 99 



in pairs, each pair alternating with the corolla segments 

 and being attached to the corolla as one or two filaments. 



When there are less than ten stamens some are arranged 

 in pairs and others singly, but always as a series of five 

 alternating with the corolla lobes. It would thus appear 

 that if we have to maintain the importance of abortion 

 we must have the primitive hermaphrodite flower with 

 numerous stamens arranged in pairs or otherwise. It would 

 by no means necessitate a complex series of changes to 

 derive the five-seried staminal whorl of the female flower 

 from that of the male, the barrenness in the anthers of the 

 staminodes being followed by a reduction of each pair to a 

 single member ; the inner stamen is always small. 



Now, let us take the case of D. Ebenum, the flowers of 

 which may be polygamous, dioecious, or monoecious. We 

 have seen that though the male inflorescence and female * *^^ 

 flowers usually occur on separate trees, examples have been 

 found where a true female flower replaced a member of a 

 male inflorescence. The staminal whorl of the female 

 flowers is constant in number, form, and orientation. There 

 are always eight epipetalous staminodes alternating with and fajif 

 opposite to the corolla segments. In the male flowers a 

 variable number of stamens occuf but coalescence of the 

 filament occurs so frequently that the resultant number of 

 groups is relatively small. In one case there were sixteen 

 stamens, either single or in groups of two and three, while in 

 another flower thirty -two stamens occurred showing various 

 degrees of coalescence, but in each of these the resultant 

 groups were eight in number and arranged so as to alternate 

 with the corolla segments. Hiern* mentions the occurrence 

 of as many as thirty-two stamens on eight filaments. 



This being the case, we have another example in which 

 the origin of unisexuality can be easily understood, since the 

 staminal whorl always forms a series of eight. The monoe- 

 cious state would represent the intermediate between a 



* Hiern, I.e., p. 208. 



