24 MISC. PUBLICATION 110, U. S. DEPT. OF AGRICULTURE 



and which, together with the lemma 

 and lodicules, incloses the stamens 

 and pistils and later the grain; (2) 

 one of the chaffy bracts on the stipes 

 of certain ferns; (3) a chaffy bract 

 on the receptacle or in the pappus 

 of some composites. Same as palet. 



Palet: See Palea. 



Palmate: Digitate. The term refers to 

 organs (e. g., leaflets) which are 



Figure 46. — Palmate 

 leaf, as in cinque- 

 foil (Potentilla sp.) 



radiately lobed or divided, suggest- 

 ing the outspread fingers of the 

 hand; as, for example, the leaflets 

 of cinquefoil, clover, lupine, and 

 horsechestnut or buckeye. (Fig. 46.) 

 A trifoliolate leaf, as in clover, is 

 3-palmate or digitate; a quinquefoli- 

 olate leaf, as in cinquefoil (Poten- 

 tilla) is 5-palmate or digitate. 

 Panicle: A compound raceme; a com- 

 pound, more or less open inflores- 



Figueb 47. — A panicle 



cence in which the lower branches 

 are typically longer and blossom 

 earlier than the upper branches. 

 (Fig. 47.) The term is sometimes 



loosely applied to any irregular com- 

 pound inflorescence. 



Paniculate: Panicled; arranged in 

 panicles ; having the form or char- 

 acteristics of a panicle, as the panic- 

 ulate inflorescence of Kentucky blue- 

 grass. 



Papilionaceous : Literally, butterflylike. 

 A term used to describe the shape 

 of the characteristic corolla of the 

 pea family. (Fig. 48.) See keel, 

 standard, and wing. 



Papilla: A diminutive nipplelike or 

 pimplelike protuberance. Typical 

 papillae may be seen, for example, 

 on the leaves of certain mertensias, 

 the seeds of certain catchflies 

 (Silene spp.) and spurges. 



Papillate : Beset with papillae. 



Papillose: Same as papillate. 



Figure 48. — Papiliona- 

 ceous corolla, as in 

 sweet pea (Lathyrm 

 odoratus) and other 

 leguminous plants : a, 

 Banner or standard ; 

 t, wing petal ; o, keel ; 

 d, pedicel 



Pappus: Thistledown; the peculiar 

 calyx limb of composites (Astera- 

 cese), etc., surmounting the achene, 

 or fruit, commonly bristlelike, awn- 

 like, or feathery, and an instrument 

 of seed dispersion by wind, animals, 

 etc. The feathery pappus of a dan- 

 delion seed is a familiar illustration. 

 (Fig. 49, a.) 



Parasite: An organism (plant or ani- 

 mal) which derives its sustenance 

 from another. Thus, mistletoes are 

 parasites of oaks, pines, and other 

 woody plants. 



Paratype: In general, one of the origi- 

 nal series of specimens in which the 

 type specimen was collected. Ac- 

 cording to some authors this defini- 

 tion applies only where the type 



