INTRODUCTION. 



29 



it is perigynous ; or when the calyx adheres to the ovary, it appears on the 

 summit of the latter, and is epigynous. In such case, when confluent with 

 the base of the style, it is called a stylopodium. The insertion of the sta- 

 mens and position of the disk always correspond, hence the same terms are 

 employed to designate the origin of the former as are employed to denote the 

 situation of the latter. 



Pistil. This consists of three parts ; the ovary or germ, the style, and 

 the stigma. The number of pistils is very various in 

 different plants ; where there is one, the flower is said 

 to be monogynous, where two, digynous, &c. (see 

 Linnsean classification.) The pistil is sometimes at- 

 tached to the receptacle by a prolongation of the sub- 

 stance of the latter, called a gynophore, as in the 

 Strawberry where the eatable part is the gynophore. 



The stigma is of a glandular nature, and is usually 

 covered with a viscid fluid ; it is destitute of a cuticle, 

 and is essential, as it receives and exercises a peculiar 

 action on the fecundatory pollen. It is called sessile 

 when the style is wanting, being then placed imme- 

 diately on the ovary. 



The style is the long cylindrical column arising from 

 the ovary and terminated by the stigma. It is some- 

 times articulated with the ovary, in which case it falls 

 off when it has performed its function ; and sometimes 

 is continuous with it, when it is persistent. It is not 

 essential, and is frequently absent. Usually it arises 

 from the summit of the ovary, but sometimes from the 

 side of it, when it is termed lateral. The ovary is the 

 lower and thicker part of the pistil, and contains the d 

 ovules. A single pistil consists of a transformed leaf 

 folded inwards, with the margin united. The line formed by the union of 

 these margins is called the ventral suture ; the opposite line, representing 

 the midrib, is termed the dorsal suture. The surface of the pistil, of course, 

 corresponds to the lower, and its interior to the upper surface of the leaf. 

 The stalk of the pistil, if present, answers to the petiole; and a prolongation 

 of the apex of the 

 changed leaf, forms lg ' 



the style. The leaf, 

 in this modified state, 

 is called a carpel. 

 When there is only 

 one cell in an ovary, 

 it has been formed of 

 a single carpel, or of 

 several with the divi- 

 sions obliterated. In 

 a many-celled ovary 

 each cell is formed of 

 a single carpel, and 

 the divisions or parti- 

 tions are called disse- 

 piments. They are Change of leaf into pistil, a Carpcl- 



formed of two layers, ^jf^*/ 18 " 1 - c DoubIe ,eaf - d 

 and are vertical ; and 



Pistil of Vaccinium amce- 

 num. a Ovarium, b Calyx. 



Placenta. e Ovules. / 

 Style, g Stigma. 



Fig. 25. 



Pistil of Coriaria myrtifolia, 

 showing distinct carpels and 

 styles. 



