606 Transactions. 



In the female flower, even in cases where one ovule is aborted, the wall 

 becomes thickened, though no stage has been noticed in which it has done 

 so if neither of the ovules matured. Some of the flowers had withered and 

 fallen, from no apparent mechanical injuries, and this pointed to the con- 

 clusion that when neither of the ovules reached maturity the flower was 

 cast off by an absciss layer being formed at the base of the pedicels. 



Ovule. 



Coming now to the development of the ovule, we find a pendulous ovule, 

 the funicle arising from the axial placenta, not, as at first appears, from the 

 top of the ovary. The ovules turn from each other, as is usual. In the 

 young buds examined the ovules had not completely achieved the anatropous 

 condition typical of the mature form. The micropyle is in these young 

 stages seen to be wide, and situated laterally, being almost at right angles 

 to the funicle. Later, by unequal growth of the cells of the funicle, the 

 ovule becomes truly anatropous. The micropyle is then almost entirely 

 roofed over by the arillus, a structure arising from the funicle. This in 

 the young bud is as large as the body of the ovule itself, and presents there 

 a rounded bulgy appearance (fig. 8). Its cells are larger than those of the 

 funicle from which it springs. As the flower develops, the cells of the arillus 

 are seen to acquire a radiating appearance, while the outer cells become 

 papillate (fig. 16). As the ovule reaches maturity these cells collapse and 

 the whole structure degenerates. It does not increase much in size through- 

 out the life of the ovule. It is present in both male and female flowers, 

 and is also seen in the hermaphrodite flowers. Here it has not the rounded 

 character, as in the male and female flowers, formed earlier, but it is more 

 gently sloping. In the female flower it completely overarches the micropvle 

 of the ovule, its papillate cells seeming to lead to the micropyle. 



Integument. 



As in UmbeUiferae generally, there is only one integument. In the 

 young ovule it is seen on both sides of the nucellus, from which it is entirely 



Fig. 7. — Longitudinal section of ovule in male bud, showing crescent-shaped integu- 

 ment. X 175. 



Fig. 8. — Longitudinal section of ovule in male bud, showing arillus and undifferentiated 

 nucellus. X ] 75. 



free, leaving a very wide micropyle. In some male buds sectioned the 

 arillus formed the largest part of the ovule, the integument being scantily 

 developed and crescent-shaped in longitudinal section (fig. 7). Later the 



