n8 CYRILLACEAE. 



9. Leaflets serrate. R. typhina. 



Leaflets deeply cut. R. typhina laciniata. 



Leaflets twice-divided. R. typhina dissecta. 



COTINUS. Smoke Tree. 



Aromatic-gummy deciduous shrubs or very small trees with 

 soft yellow wood with crowded moderate ducts in the spring 

 growth, dotted or transverse groups of minute ducts in the 

 summer growth, and fine but evident medullary rays ; roundish 

 twigs ; alternate raised crescent-shaped or 3-lobed rather small 

 leaf-scars with 3 or 5 bundle-traces ; entire moderately large 

 slender-stalked simple leaves ; inconspicuous polypetalous flow- 

 ers in terminal panicles ; and small dry fruits on feathery slen- 

 der stalks. Frequently placed under Rhus. 



1. Leaves rather round and small (scarcely 8 cm. long). 2. 

 Leaves elliptical and large (10-16 cm. long). C. americanus. 



2. Not weeping. 3. 



Weeping. C. Coggygria pendulus. 



3. Leaves somewhat pubescent. C. Coggygria pubescens. 

 Leaves glabrous. 4. 



4. Hairs of inflorescence pale. C. Coggygria. 

 Hairs of inflorescence purple. C. Coggygria atropurpureus. 



Family CYRILLACEAE. 



A small family of no considerable use : the following some- 

 times found in shrubberies. 



CYRILLA. Black ti-ti. 



Subevergreen shrubs or small trees with rather hard brown- 

 ish wood with minute diffused ducts and fine but evident me- 

 dullary rays ; rather slender 3-angled twigs ; alternate somewhat 

 raised triangular small leaf-scars with I bundle-trace; solitary 

 sessile small buds with several loose pointed scales : simple mod- 

 erately small cuneately short-stalked leaves ; small colorless per- 

 fect polypetalous flowers densely clustered in racemes from the 

 winter nodes ; and small ovoid capsules on reflexed pedicels. 

 Leaves subacuminate, revolute, raised-veiny. C. racemiflora^ 





