462 APPENDIX. 



Pinnae, the leaflets or little leaves of a pinnated leaf. 



Pinnatifid; a leaf is said to be pinnatifid when it is divided nearly to the 

 mid-rib, that is, not quite pinnate ; as in Feverfew, Polypody, &c 



Pisiform, formed like a pea. 



Pistil, the central part of a flower, consisting of three parts — the base or 

 germen (ovary) ; the intermediate columnar body or style and the 

 summit or stigma. The style is sometimes absent, and then the 

 stigma is said to be sessile. There may he one or many pistils, and 

 according to their number so are the orders of the Linnaean system in 

 most of the classes. 



Pistilliferous, containing pistils only ; as the outer florets of Daisy. 



Pith, medulla ; the substance occupying the centre of a stem or shoot. 



Placenta, that part of a seed-vessel to which the seeds are attached. 



Plaited, folded like the plaits of a fan ; as the corolla of Thorn-Apple. 



Plane, flat, having a perfectly level surface ; as the leaves of Yellow Flag. 



Plano-convex, flat on one side, convex on the other. 



Plumose, feathery. 



Plumule, or Gemmule, the minute body situated between the cotyledons 

 in the embryo of a seed. 



Pod, see Legume and Silique. 



Pollen, the pulverulent matter contained in the anthers of a flower, com- 

 posed of globules containing the fecundating fluid. 



Polyandrous, having more stamens than twenty inserted on the receptacle. 



Polygamous, applied to plants which produce flowers with stamens only, 

 pistils only, and both stamens and pistils, on the same individual, or 

 on two or three distinct plants of the same species. 



Polypetalous, having many petals. 



Polyspermous, bearing many seeds. 



Pome, a fleshy fruit, two or more celled, indehiscent, the seeds enclosed in 

 dry cells ; as the common Apple. 



Pores, apertures in the cuticle of a leaf, &c, by which transpiration is ef- 

 fected ; also small holes in the anther through which the pollen is 

 ejected. 



Pouch, a short, flat, broad seed-vessel, a silicle ; also a little sack or bag 

 at the base of some petals and sepals. 



Praemorse, appearing as if bitten off. 



Pressed, close, not spreading. 



Prickles, rigid, sharp-pointed, conical bodies, capable of being easily de- 

 tached from the part on which they grow, and thus differing from 

 spines or thorns, which proceed from the woody fibre, and are persist- 

 ent. Prickles are abundant on the Bramble, Rose, &c. 



Prismatic, prism-shaped ; having several longitudinal angles and inter- 

 mediate flat faces. 



Procumbent, spreading on the surface of the ground ; as the stems of Bear- 

 berry, Chamomile, Periwinkle. 



Prostrate, lying upon the ground, or other surface ; as the stem of Penny- 

 royal. 



