GLOSSARY 223 



Pinnate. A compound leaf with the leaflets arranged on each side of a com- 

 mon axis. 



Pinnatifid. Pinnately cleft. 



Pinnule. A division of a pinna. 



Pistil. The female reproductive organs in the higher plants. 



Pistillate. Provided with pistils, and usually implying the absence of sta- 

 mens. 



Placenta. An ovule-bearing surface. 



Plicate. Folded lengthwise. 



Plumose. Plume-like ; having fine hairs on each side. 



Plumule. The growing point of the embryo. 



Pod. A dry, dehiscent fruit. 



Pollen. The fertilizing bodies contained in the anther. 



Pollinia. The waxy pollen-masses of orchids and milk-weeds. 



Polygamous. Bearing both perfect and imperfect flowers on the same plant. 



Polypetalous. Having separate petals. 



Pome. A fleshy fruit like an apple. 



Procumbent. Lying flat on the ground. 



Prothallium. The sexual generation of Pteridophyta. 



Puberulent. Short hairy. 



Pubescent. Covered with hairs, especially if short and soft. 



Punctate. Dotted with translucent spots or pits. 



Pungent. Tipped with a rigid point. 



Pyriform. Shaped like a pear. 



Raceme. An elongated flower cluster in which the flowers are pedicelled and 



the lower bloom first. 

 Racemose. Borne in racemes. 

 Rachilla. The axis of the spikelet in Gramineae. 

 Rachis. The axis of a spike, raceme or compound leaf. 

 Radiate. Bearing ray-flowers ; spreading from a common center. 

 Radicle. The rudimentary stem in the embryo. 

 Ray. A branch of an umbel ; a marginal flower when distinct from the 



others. 

 Receptacle. That part of the axis bearing the reproductive organs ; or the 



collective flowers in Compositae. 

 Recurved. Backwardly curved. 

 Reflexed. Abruptly recurved. 



Regular. Having all parts of the same nature similar. 

 Reniform. Kidney-shaped. 

 Repand. Having a wavy margin. 

 Reticulate. Netted- veined. 

 Retrorse. Turned back or downward. 

 Retuse. Having a shallow notch at the rounded end. 

 Revolute. Rolled backward. 

 Rhachis. The same as rachis. 

 Rhizome. A rootstock. 



Ringent. The gaping mouth of a bilabiate corolla. 

 Rostrate. Beaked. 

 Rotate. Flat and round in outline. 



