MALACEAE 137 



I. Leaves dull; veins deeply impressed above. 



3. Thorns up to 7 inches long; leaves glabrous 



above C. cuneiformis (Marsh.) Egglest. 



3. Thorns up to 2 inches long; leaves pubescent 



C. punctata J acq. 



C. Leaf blade widest at the middle. 



4. Leaf veins deeply impressed above. 



5. Leaves thin; thorns V/i to 2 inches long 



C. tomentosa L. 



5. Leaves leathery, thorns up to Zli to 4 inches long. 

 6. Leaves elliptic, acute at both ends 



C. succulenta Schrad. 



6. Leaves broader, mostly rounded at the apex. 

 7. Calyx lobes edged with stipitate, bright red 



glands (fig. 31) C. illinoiensis Ashe 



7. Calj-x lobes bearing only minute, dark glands 



C. macracantha Lodd. 



4. Leaf veins not deeply impressed above. 

 8. Margins of calyx lobes glandular. 



9. Leaves leathery, U/i to 2 inches long, midrib 



green (fig. 31) C. rotundifolia Moench 



9. Leaves firm, 1 to I14 inches long, midrib yellow 

 (fig. 31) C. Marga'retta Ashe 



8. Margins of calyx lobes glandless. 



10. Thorns up to 1 inch long; midrib yellow 

 below C. viridis L. 



10. Thorns 1 to 1^ inches long; midrib red 



below C. nitida (Engelm.) Sarg. 



B. Leaf widest toward the base. 



D. Calyx lobes entire ; leaves relatively sma.ll. 



11. Leaves glabrous above, blue green; fruit hard and 

 covered with bloom. 



12. Fruit green until nearly ripe (fig. 32) 



C. pruinosa (Wendl.) K. Koch 



12. Fruit orange red, green blotched, dark dotted 

 C. conjuncta Sarg. 



11. Leaves pubescent or scabrous above; fruit soft and 

 without bloom. 



13. Leaf teeth tipped with bright red glands 



C. lucorum Sarg. 



13. Leaf teeth lacking such glands. 

 14. Fruit subglobose. 



15. Fruit reddish purple, pale dotted 



C. cyanophylla Sarg. 



15. Fruit scarlet, not conspicuously dotted 



G. sextilis Sarg. 



14. Fruit obovoid, bright reddish purple 



C. apiomorpha Sarg. 



D. Calyx lobes toothed ; leaves larger (1 to 4 inches long). 

 16. Mature leaves glabrous. 



17. Calyx not enlarged on the fruit. 



