86 PISTIL. 



interior of these cells, and produce the molecular motion by 

 their interior action. The point as to their existence is as 

 far from being settled as ever. Some botanists, speak of 

 them as though there was no doubt of it, while others treat 

 the subject quite cavalierly, by applying to it the not very 

 scientific term, " ce roman !" 



99. The larger particles of the fovilla, have been coirtjider- 

 ed as the necessary organs of impregnation. It is conjec- 

 tured that they make their way into the ovule, and through 

 their agency acting as potential organs, tbe embryo is pro- 

 duced. This needs confirmation. Schleiden and Endlicher 

 take entirely different views of the subject. They believe 

 that the incipient embryo is in the pollen tube which makes 

 its way into the ovule merely for finding a proper location 

 for its development. These are some of the notions prevalent 

 on this highly interesting and important part of the vegetable 

 economy. Which, or whether any of them, will ever be es- 

 tablished as true, remains for future discoveries. We shall 

 notice some points more fully in the article on Fertilization. 



Pistil. 



100. The pistil is the center of the flower, and forms the 

 summit of the axis of growth. It is like the other floral or- 

 gans, a modification of the leaves. The pisljl is divided into 

 three parts, the germ, (which becomes the ovary,) style and 

 stigma. 



The stigma, fig. 104, c, is the summit of 



^ the pistil, and is the extremity of the midrib 



of the leaf which composes the pistil. It is 

 10^ I *^® ^^^y I^^'^ except the spongioles, that is 



--b not covered with the cuticle. It is generally 

 glutinous and moist, thus causing the pollen 

 grains to adhere to it, and at the same time 

 yielding enough moisture to make them put 

 _ forth the pollen tubes. It is covered with 



papillae which are undoubtedly the cells of the parenchymous 

 substance of which it is composed, and is the channel through 

 which, in all cases, the fecundating matter is transmitted to 

 the ovule. It varies much in form, or if with some botanists, 

 we consider the stigma only a surface fitted for the reception 

 of the pollen and transmission of the fertilizing substance, 

 the variety of forms of stigma usually described by botanists 

 would properly come under the style. Lindley remarks that 

 nothing, properly speaking, is a stigma except the secreting 

 surface of the style. This surface is usually on the expand- 



