CEYLON. 
103 
corolla segments. The male flowers possess a very large 
number of stamens, there being rarely less than sixteen and 
very often over twenty-two in each flower. The stamens 
are nearly all in pairs, each having the inner stamen shorter 
than the outer and with the filaments of each pair united 
throughout the greater part of their length; sometimes 
three anthers are supported on the same united filament. 
In some flowers I have found eight pairs arranged 
opposite to and alternate with the corolla segments, but in 
by far the greater number of flowers the pairs of anthers 
are in excess of twice the corolla segments. In one flower 
possessing ten pairs of stamens there was always a pair 
alternating with the corolla segments; the remaining six 
pairs were arranged as two pairs on each of two corolla 
segments and a separate pair on each of the other two 
corolla segments. 
If we allow that in the production of the female flower 
sterilization and reduction in number has occurred, we 
fan easily understand the derivation of the four-seried 
flower from one having staminal members alternate with 
and opposite to each corolla segment, as is now seen in 
male flowers possessing eight groups of stamens. Hence 
the evolution from the hermaphrodite type is rendered 
possible. 
In D. Embry opteris we have a difficult case, since there is 
practically nothing to connect the four staminodes of each 
female whorl with the male ring of thirty or forty stamens. 
The indefinite stamens in each male flower are sometimes 
separate, at other times united in pairs, and may be epipetal¬ 
ons or hypogynous. In D. affinis the conditions are almost 
the same as in D. Embryopteris, since the male staminal 
whorl consists of sixteen or more members apparently 
disposed without any definite relation to the accessory 
whorls. The stamens occur in pairs or are single, and form 
an epipetalous ring or hypogynous group. Each female 
flower possesses from six to eight staminodes arranged on 
the corolla opposite to and alternate with its segments. 
