ORGANS OF REPRODUCTION. 



265 



of the upper surface of the lamina of the leaf, merely modified to 

 adapt itself to the peculiar conditions under which it is placed, 

 in the same way as is the case with the epithelium forming the 

 lining of the ovary. When the carpel is fully matured, that is. 

 at the period when it is adapted for recei^nng the influence of 

 the pollen, the canal of the style becomes further obstructed by 

 a number of lengthened filiform cells {fig. 582, f,f), which have 

 been sometimes confounded with pollen-tubes, but from which 

 they are readily distinguished by being twice or thrice their 

 diameter. At the period of fecundation, these cells, as well as 

 those of the stigma and canal of the style generally, secrete a 

 peculiar viscid fluid containing gum or sugar, or both, which 

 is called the stigmatic fluid. The loose tissue which thus lines 

 the canal of the style, with the filamentous elongated cells which 

 are developed in it at the period of fecundation, and the secreted 

 fluid, together form a very loose humid tissue, to which the name 

 of cuiuhicting tissue has been given, because from its loosened 

 nature and nourishing properties it serves to conduct the pollen- 

 tubes down the styles to the placenta and ovules, as will be ex- 

 plained hereafter. 



Fig. 586. 



Fig. 587. 



Fig. 588. 



Fig. 586. Tentral view of the pistil of J.<Jopj/rMm bitervafnm., sliowing the 

 double stigma. Fig. 5S7. Pistil of Wlieat surrounded by three sta- 

 mens, and two sauannilae, .<!, p. Two feathery styles arise from the top 



of the ovary. Fig.oSS. Pistil of Dianthus Cnrophyllns on a stalk, q, 



called the gynophore. below which is the peduncle. On the top of tlie 

 ovary are two styles, the lace of which is traversed by a continuous 

 stigmatic surface. 



The Stigma. — The tissue of the stigma is analogous to that 

 found in the interior of the style, and just described under the 



