ORGAKS OF EEFRODUCTION. 



27] 



sometimes with hairs. The parenchyma between the epithe- 

 lium and epidermis, me. corresponds to the general parenchyma 

 of the leaf, which is similarly placed. Where the margins of 

 the carpellarj leaf meet and unite at the yentral suture, a layer 

 of cellular tissue is deyeloped, which forms a more or less pro- 

 jecting hne in the ca\ity of the ovary, called the placenta 

 (fiy. 429, p), to which the oyules are attached. This placenta is 

 essentially double, the two halves being deyeloped from the two 

 contiguous margins of the carpellary leaf. 



The style has been considered by some botanists, as a prolon- 

 gation of the midrib, but fi-om the arrangement of its tissue it is 

 to be regarded rather, as a prolongation of the whole of the upper 

 portion of the lamina rolled inwards and united. It consists of 

 a cylindrical process of parenchyma, traversed by distinct vas- 

 cular bundles, which are arranged so as to form a sort of sheath 

 at its circumference. These bundles are a continuation of 

 those of the ovary, and proceed upwards without branching 

 tOAvards the apex of the style, but always terminate below that 

 point. The style is invested by epidermis continuous with that 

 of the ovary, and furnished occasionally like it, with stomata 

 and hairs. 



Upon making a transverse or vertical section of the style, we 

 find that it is not a sohd body as we might have supposed, but 

 that it is traversed by a very narrow canal (Jigs. 58(», d, and 578, 

 tc), which communicates below A^ith the cavity of the ovary, and 

 above Avith the stigma. This canal is, either ahvays entirely 



Fig. 580. 



Fig. .581. 



Fig. 579. Vertical section of the flower of Epipactis 

 latifolia. a. One of the divisions of tlie perianth; 

 c. Stamen ; e. Ovules; x. Stigma; can. Canal 

 leading from the stigma to the interior of the 



ovary. From Schleiden Fig. 580. Transverse section of the style of 



the Crown Imperial {Fritillaria imperialis). d. Canal in its centre lined 



by projecting papillse. From Jussieu Fig. 5S\. Section showing the 



structure of tlie canal of the style in Campanula. From Jussieu. c, c. 

 parenchymatous cells forming its walls, traversed by spiral vessels, v ; p, p. 

 variously-formed loosely aggregated cells; /, /. elongated filiform cells, 

 which with the former more or less obstruct the canal. 



