The Thorn Trees 



447 



becoming smooth above, broad; young foliage 

 red-bronze. 

 Nutlets usually 4 or 5; leaves hairy. 

 Nutlets 5; leaves and corymbs woolly-hairy. 

 Leaves often deeply lobed. 



Flesh thin; nutlets 5; leaves thin; leaves scab - 

 rate above when mature, elliptic-ovate; 

 fruit depressed globose, red. 

 Flesh thick; nutlets usually 5; fruit large, hairy, 

 subglobose, oblong or pear-shaped, red, 

 edible; corymbs hairy, many-flowered; 

 leaves thin, yellow-green, broad, promi- 

 nently lobed; young foliage yellow- 

 green. 

 Leaves and young twigs hairy. 



Fruit red or crimson, sometimes 25 mm. 

 thick; nutlets 7 to 9 mm. long, 10 mm. 

 thick; leaves' 4 to 10 cm. wide, 4 to 13 

 cm. long. 

 Fruit scarlet, sometimes 15 mm. thick; nut- 

 lets 6 to 8 nmi. long, 7 to 9 mm. thick; 

 leaves 3 to 8 cm. wide, 3 to 8 cm. long. 

 Leaves and young twigs densely woolly- 

 hairy; fruit bright cherry-red; nutlets 6 

 to 8 mm. long, 8 to 11 mm. thick, 

 aa Leaves conspicuously 3- to 5-lobed; fruit small, depressed- 

 globose, red; nutlets 5, with conspicuous calyx-scar; flesh 

 thin; leaves half-leathery, bright green above; corymbs 

 smooth, many-flowered. 

 H Fruit ripening in spring; sinuses between nutlets deep; nest 

 of nutlets shorter than thick; nutlets 5; fruit subglobose, 

 red; flesh thick, soft, edible; corymbs woolly-hairy, few- 

 flowered; leaves rusty woolly-hairy, 

 tt Nest of nutlets without sinuses; nutlets 2 to 5, cal3^-scar con- 

 spicuous; fruit small, oblOTg, scarlet; corymbs many- 

 flowered; leaves hairy, veins extending both to the points of 

 the lobes and the bottoms of the sinuses. 

 Nutlets 2; leaves deeply cut. 

 Nutlets s; leaves entire. 

 ** Fruit blue-black; nest of nutlets without sinuses; nutlets 3 to 5, caljrx- 

 scar conspicuous; nest of nutlets shorter than thick; fruit sub- 

 globose; flesh thin; corymbs smooth, many-flowered; leaves 

 smooth, half -leathery, dark green and shining above, narrowed 

 at the base, veins extending both to the points of the lobes 

 and the bottoms of the sinuses. 

 B. Nutlets with a shallow cavity on each inner face, or cavities on indi- 

 vidual nutlets sometimes faint or wanting; fruit red. 

 Nutlets usually 3 to 5; leaves thin but firm, bright yellow-green 

 above. 

 Nutlets 3 or 4; leaves and corymbs nearly smooth. 

 Nutlets s; leaves, corymbs and fruits densely hairy. 



31. C. Pringlei. 



32. C. texana. 



33- C. gravida. 



34. C. mollis. 



35. C. canadensis. 



36. C. lanuginosa. 



37. C. Phanopyrum 



38. C. <estivalis. 



39. C. Marshallii. 



40. C. spaihulata. 



41. C. brachyacantha. 



42. C. Columbiana. 



43. C. laurentiana. 



