850 GLOSSARY. 



Pappus : the bristles, scales, teeth, or chaff crowning the achenium 



of many Compositse. 

 Parasite: a plant situated on another from which it draws its 



nourishment. 

 Parasitic : drawing nourishment from another plant. 

 Parenchyma : the soft tissue in the leaf ; tissue whose cells are 



roundish, or if elongated not having pointed ends. 

 Parenchymous : having or like parenchyma. 

 Parietal : attached to or belonging to the wall. 

 Parted : divided almost to the base or midrib, etc. 

 Parthenogenesis : production of seed without the intervention of 



pollen. 

 Pauei (as a prefix) : few. 



Pectinate : finely divided, like the teeth of a comb. 

 Pedate : like a bird's foot. 



Pedicel : the branch of 'the peduncle which supports the flower. 

 Pedicellate (or Pedicelled) : having a pedicel. 



Peduncle : the flower-stem or stalk supporting one or many flowers. 

 Peltate : shield-shaped. 



Penta (as a prefix) : five ; as pentamerous, five-parted, etc. 

 Pepo : the Grourd fruit, or fruit like the Melon or Cucumber. 

 Perennial : persisting from year to j'ear. 

 Perfect flower : one with both stamens and pistils. 

 Perfoliate leaf: with the base extending around the stem so that the 



latter appears to pass through the leaf. 

 Peri (as a prefix) : around. 

 Perianth : the floral envelope, especially when the distinction 



between the calyx and corolla is not evident, as in Lilies. 

 Perihlem : the portion immediately under the dermatogen and which 



becomes the cortex. 

 Pericarp : the wall of the ovary or fruit. 

 Periderm : a continuous corky layer surrounding the stem. 

 Peridium: an investing cellular layer or wall, as in case of the fruit 



of some Fungi, as Puff-balls, Cluster-cups, etc. 

 Perigynoiis : situated on the calyx. 

 Perisperm : the portion of reserve material of the seed which, in a 



few cases, is stored up outside of the embryo-sac. 

 Peristome : the circle of teeth around the orifice of the capsule or 



theca of Mosses. 

 Persislent : remaining longer than the usual time. 

 Perithecium : the wall of the fruit or Sporocarp of some ascomycetous 



Fungi. 

 Petal : one of the parts or leaves of the corolla. 

 Petiolate : having a petiole. 

 Petiole : the stem or stalk of a leaf. 

 Phcenogam : a plant which produces flowers and seeds. 

 Pha-nogamous : having flowers and producing seeds. 

 Phellogen: cork-cambium; meristem which produces cork-cells. 

 Phenogam : same as phsenogam. 

 Phloem ! the bast portion of a fibro-vascular bundle. 



