RUTACEAE. 



165 



PHELLODENDRON. Cork Tree. 

 (Family Rutaceae). 



Small trees with spongy soft 

 bark: deciduous. Twigs moderate, 

 rounded: pith moderate, brown, 

 continuous: bark yellow when cut. 

 Buds solitary, sessile, half-ellip- 

 soid, compressed from the sides, 

 silky with red or bronzed hairs 

 so as to mask the overlapping of 

 the 2 scales. Leaf-scars opposite 

 or the pairs separated, horseshoe- 

 shaped, raised, rather large: bun- 

 dle-traces 3, often compound. 



Winter-characters of Phelloden- 

 dron ammurense are pictured by 

 Schneider, f. 97; and Shirasawa, 

 272, pi. 10. 



Phellodendron and Evodia dif- 

 fer from the other Rutaceae here 

 considered in having their leaf- 

 scars opposite or in broken decus- 

 sating pairs, and not alternate 



on the stems. Winter twigs of Ptelea, which might be mis- 

 taken for those of the cork tree, are easily distinguished by 

 this character. 



Though in some respects well suited to cultivation, the 

 cork trees possess the great demerit of holding their black 

 berry-like fruits late into the season so that, like the black 

 cherry in summer, they become an unusual nuisance until the 

 last fruit has fallen. 



1. Twigs orange: bark of trunk corky. P. amurense. 

 Twigs red or purple-brown: bark of trunk not corky. 2. 



2. Twigs glabrous. (1). P. sachalinehse. 

 Twigs somewhat hairy above. P. chinense. 



