PL AT ANUS 519 



with very long filaments and versatile anthers containing much powdery 

 pollen; G usu. (2), 2-loc., with i oc semi-anatr. ov. on axile plac. 

 Fr. a membranous caps., opening with a lid cut off by a peripheral 

 dehiscence, or sometimes, a nut surrounded by the persistent calyx. 

 Embryo straight, in fleshy endosp. Genera: Plantago, Littorella, 

 Bougueria. See P. and L. 'for details. The relationships of the P. 

 are difficult to make out. The fl. is usu. regarded as derived from a 

 5-merous type in the same way as that of Veronica, and most authors 

 agree in regarding the P. as degraded forms allied to Scrophulariaceae, 

 Labiatae, &c. The wind-pollination of the flr. is also an evidence of this. 

 Plantaginales. The yth order of Sympetalae. 

 Plantagineae. (Bff.)= Plantaginaceae. 



Plantago iTourn.) L. Plantaginaceae. 200 cosmop. ; 5 in Brit., good 

 illustrations of the gen. P. major L. (greater plantain) is a perennial 

 with a thick root and a rosette of large erect L, in whose axils arise 

 the infls. (spikes). Fl. protog. , the stigmas protruding from the bud ; 

 the sta. appear later. Wind-pollination is the rule, but insects some- 

 times visit them for pollen. The fruit-spikes are often given as food 

 to cage-birds. P. media L. (hoary plantain) shows similar general 

 features, but the 1. lie flat on the ground (hence it is a troublesome 

 weed) ; they exhibit the 3/8 phyllotaxy (q.v.) very clearly. The rl. is 

 more conspicuous than P. major and has a pleasant scent, and though 

 primarily wind-pollinated, is largely visited for pollen. It is some- 

 times gynodioec. (cf. Labiatae). P. lanceolata L. (rib-wort plantain) 

 has narrow erect 1.. and fls., also gynodioec. P. Coronopns L (buck's- 

 horn plantain) is xero. with hairy 1., growing in sandy places. Many 

 S. Am. sp. show marked xero. characters dense tufting, small hairy 

 1., often grooved on the lower surface (cf. Ericaceae), &c. P. maritima 

 L. (the sea-side plantain) has linear fleshy 1. ; it is found at high levels 

 in the Scottish Mis., though rarely in the intermediate regions. 



The seeds of many swell up when wetted and become mucilaginous 

 (cf. Linum). Those of P. Psylliiim L. (Medit.) are used in silk and 

 cotton manufacture ; they have also been used in medicine. 



If the young growing inrl. be vigorously shaken, when left to itself 

 it droops and only becomes erect again alter some time. The strain 

 stretches the young cell walls beyond their limit of elasticity. 

 Plantain, Mnsa paraiiisiaca L. (in India &c., incl. Musa Sapientitin L., 

 the banana), Plantago; bastard- (Vf.l.),fJeliconia\ water -, A/isi/ia 

 Plantago L. 

 Platanaceae (P., BH.}. Dicots. (Archichl. Resales; Unisexuales 



BH.}. Only gen. Platanus (q.v.). Relationships obscure. 

 Platanthera Rich. (Habenaria^.p- BH.}. Orchid, (n. i). 80 N. temp., 



trop. 



Platanus (Tourn. ) L. Platanaceae. 5 N. temp., incl. the plane-tree, 

 P. oriental is L. The bark scales off every year, leaving a smooth 

 surface. The axillary bud is developed under the base of the petiole, 

 which fits over it like an extinguisher. The stipules are united round 

 the stem. Fls. monoec. in pend. heads, wind-fert. K, C 4 or 3, A 4 or 3, 

 opp. sepals, G 4 or 3 ; ovules orthotr., pend. Multiple fr., each cpl. 

 giving a caryopsis, often winged. Seed album. The wood of the plane 

 is useful, and also that of the buttonwood of N. Am. P. occidentalis L. 



