GLOSSARY OF BOTANICAL TERMS. 



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Phyllode (phy'lodium) , a flat dilated petiole, fulfilling the functions of a leaf, 



as in many Acacias. 

 Pinna, a primary division of a pinnate leaf ; a leaflet. 

 Pinnate, a compound leaf whose leaflets are arranged on each side of the common 



petiole or axis. When there is an odd terminal leaflet, the leaf is called 



unequally pinnate or imparipinnate. Also applied to lateral nerves arranged 



on each side of the midnerve of a leaf. 

 Pinnatifid, a leaf cut into lobes about half-way to the midrib. 

 Pin nati partite, cut more than half-way to the midrib. 

 Pinnatisect, cut into segments nearly or quite to the midrib, but the segments 



not separating easily, as leaflets do. 

 Pinnule, the second or third division of a leaf which is twice or thrice pinnate or 



pinnatisect. 

 Pistil or gynoeeium, the innermost and female part of the flower, consisting of 



one or more carpels. When there is only one carpel, the terms carpel, pistil, 



and gynoeeium are synonymous. When two or more carpels adhere by their 



ovaries the pistil or gynoeeium is compound or syncarpous (fig. 1). When the 



carpels are separate the pistil is apocarpous. 



Fig. 2. — Vertical section of flower of 

 Linum marginale. st.br. style -branches or 

 free part of 5 united styles ; st. style ; anth. 

 anthers opening in parallel slits ; sep. sepals ; 

 pet. lower part of one petal, the others 

 removed ; fil. filament ; ovary, superior 

 5-ceJled compound ovary, of 5 united car- 

 pels ; ovule, anatropous pendulous ovule ; 

 fun. funicle ; mp. superior (epitropous) 

 micropyle ; nuc. nucellus ; rh. ventral 

 rhaphe, i.e., from the position of the ovule 

 the rhaphe is turned towards the ventral 

 suture of the carpel ; chal. chalaza ; ped. 

 pedicel. 



Placenta, part of the ovary to which the ovules are attached by their funicles. 



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



Plumose, when a hair or similar organ branches into rather long spreading 



secondary hairs, arranged irregularly or in two opposite rows like the barbs 



of a feather. 

 Pod, (1) the legume of Leguminosae, a dry fruit formed of a single carpel; 



(2) the siliqua and silicule of Cruciferae, a dry fruit composed of two 



carpels separated by a partition. 

 Pollen, see stamen. 

 Pollen-mass (pollinium), pollen-grains cohering by a waxy texture or fine threads 



into a single body. 

 Polygamous, when the same plant bears male, female, and bisexual flowers. 

 Posterior, the parts of a flower nearest to the axis of the branch. 

 Prickle, sharp excrescence arising from the bark and detachable without tearing 



the wood. 

 Procumbent, spreading along the ground, but not so closely as prostrate. 



