XIl] OVARY AND OVULES 103 



Here, then, we find that the pistil of our Pea, 

 Laburnum, Plum, &c., consists of a box-like structure 

 composed of one carpel {monocarpellary) which com- 

 pletely encloses in its cavity one to several ovules, and 

 which terminates in a style ending in a stigma. Such a 

 box is called an Ovary, because it contains the ovule or 

 ovules : and an ovary always has a stigma but not always 

 a style, the stigma being sessile on the ovary if the style 

 is absent. 



If we now look at the pistil of the Buttercup that of 

 a Clematis, or a Strawberry, Blackberry, Raspberry, &c., 

 would show the same we find on the raised central 

 termination of the floral axis not one, but many carpels, 

 each essentially like that of the Pea, Plum, Cherry, &c., 

 just examined. (See Fig, 14.) It is true that they are 

 very small, and each contains but one ovule : nevertheless 

 each is a box-like ovary with a minute hook-like termina- 

 tion ending in a stigmatic surface, and the only essential 

 difference is that in this case the style is so short that 

 the stigma is sub-sessile, and that there are numerous 

 separate carpels {polycarpellary), each forming one closed 

 ovary containing an ovule. 



That portion of the inside of the ovary to which the 

 ovules are attached is termed the 'placenta; so that in 

 the Pea, Laburnum, &c., the placenta is on the ventral 

 suture, and the placentation i.e. the mode of arrangement 

 of the placentae is sutural. In other cases it is hasal, 

 and there are yet other forms met with. 



We see then that an essential and fundamental differ- 

 ence between the carpel and ovules of a Conifer and of a 

 higher flowering plant is, that, whereas in the former the 

 carpel is open and has the ovules exposed, naked, on its 

 surface, in the latter the carpels are closed and cover up 

 the ovules as in a box. Hence the Conifers are termed 



