730 PHARMACEUTICAL BOTANY 
PEeriG’yNous.—Applied to stamens and petals when they are adherent to the calyx 
throat, and so borne around the gynoecium. 
PER’IsPERM.—The nourishing tissue of some seeds outside of the embryo sac and 
representing the nucellus of the ovule, which during maturation has become 
laden with nutriment. 
Per’IstroME.—The teeth around the mouth of the capsule in mosses. 
PeriTHE’c1uM.—The receptacle containing asci in certain Ascomycetes. 
Persist/ENT.—Applied to parts of the flower which remain until the fruit ripens or 
to leaves which remain on the plant over winter. 
PerR’sONATE.—Applied to a bilabiate corolla which has its throat closed by a convex 
projection on the base of the lower lip. 
Pet’AL.—One of the floral leaves of the corolla. 
Pet’ALomp.—-Of some other color than green. Having the color of a petal. 
Pet’1oLe.—A leaf stalk. 
Per‘1oLuLe.—tThe stalk of a leaflet. 
PuEL’LODERM.—Secondary cortex containing chloroplasts and formed by the cork 
cambium or phellogen on its inner face. 
Pue.’LocenN.—The meristem which gives rise to cork and frequently secondary 
cortex; cork cambium, 
Puio’em.—That part of a vascular bundle which contains sieve tissue and fre- 
quently bast (phloem) fibers. 
Putoroctu’cin.—A white crystalline substance having the formula of CsH»Os, 
obtained by the decomposition of phloretin and from certain gummy extracts 
and used with hydrochloric acid as a test for lignin. 
Puycocy’Anin.—The blue pigment found in the Cyanophycez (Blue Green Algz). 
PuycOERYTH’RIN.—The red pigment occurring in the Rhodophycee (Red Aigz) 
and Cyanophyceze (Blue-green Algz). 
PuycopH#'In.—The brown pigment found in the Phezophycez (Brown Algz). 
PuycoxAn’THIN.—A yellowish pigment occurring in some Algz. 
PuyLLoc.a’pe.—A flattened branch which resembles a leaf, as in Ruscus. 
Puy.’Lope.—A dilated petiole which functions as a leaf blade. 
Puy.’/LoTAxy.—The arrangement of leaves on stems. 
PHYLLOXAN’THIN.—See xanthophyll. 
Puy.Loc’Eeny.—The history of the race. 
Puys’10LoGy.—The science which treats of the functions of living organisms. 
Puyto’GLosu.ins (Crystalloids).—Crystal-like bodies of protein composition found 
in aleurone grains. 
Puy’ton.—A term given by Gaudichaud to an internode with a node at its upper 
extremity which bears one or more leaves, in the axils of which buds may 
appear. é 
Pic’ments.—Coloring substances found in cells. 
Pi’‘Leus.—The cap of a toadstool. 
Puuur’eRous.—Bearing hairs. 
Priose’.—Covered with long, straight and scattered hairs. 
Pin’NATE.—Applied to compound leaves when the leaflets are ne ie the 
mid-rib. 
PINNAT’IFID.—Pinnately-cleft. 
PINNATIPAR’TITE.—Pinnately-parted. \ 
PrnnaT’isect.—Pinnately-divided. ; 
