144 



ARBORETUM ET FRUTICETUM BRITANNICUM. 



Stamens 45, very short. Style short. Fruit compressed, indehiscent, 

 samara-like, turgid, 2 3-celled. Seeds oblong. (Don's Mill.) 



Leaves compound, alternate, stipulate, deciduous ; pinnate, 3- rarely 5- 

 foliolate, with pellucid dots, the lateral leaflets inequilateral. Flowers 

 whitish, cymose : cymes corymbed or panicled. Deciduous shrubs or low 

 trees, natives of North America and Asia. There is only one species in 

 British gardens, which is of the easiest culture, and is propagated by seeds 

 and cuttings, put in in autumn, and covered with a hand glass. 



1 an 1. P. TRIPOLI A'T A L. The three-leafleted Ptelea, or Shrubby Trefoil. 



Identification. Lin. Sp., 173. ; Willd. Sp. PI., 1. 670. ; Dec. Prod., 2. p. 82. ; Don's Mill., 1. p. 806. ; 



Tor. and Gray, 1. p. 215. 



Synonymes. Orme de Samarie a trois Feuilles, Fr. ; dreyblattrige Lederblume, Ger. 

 Engravings. Dill. Elth., t. 122. ; Schmidt Arb., 2. t. 76. ; the plate in Arb. Brit., 1st. edit., vol. v. ; 



and our fig. 193. 



Spec. Char., Sfc. Leaf of three leaflets that are ovate acute, the middle one 



much tapered towards its base. Flowers in corymbs, usually tetrandrous. 



(Dec. Prod.} A low tree or shrub. Lake Erie to Florida and Texas. 



Height 6ft. to 10 ft. Introd. 1704. Flowers whitish; June and July; 



Capsules greenish ; ripe in October. Decaying leaves of a remarkably clear 



rich yellow. Naked young wood dark purplish brown. 

 Varieties. 



2 & P. t. 2 pentaphylla Munchh. has 5 leaflets, H. S. 

 at P. t. 3 pubescens Pursh has the leaflets pubescent. 



When this plant is pruned up with a single stem, it forms a handsome low 

 tree with a hemispherical head ; but in British gardens it is more frequently 



193. Ptfclea trifoliata. 



found as a large shrub, with numerous stems proceeding from the rootstock. 

 The shoots and leaves pubescent when young. Ovary of the staminate 

 flowers abortive. Odour of the flowers disagreeable. Capsules with flattened 

 wings, somewhat resembling those of the elm. 



Other Species of Ptelea. P. Baldwmu is described by Torrey and Gray as 

 a shrub not more than a foot high, but it has not yet been introduced 



