BUCKTHORN FAMILY 461 



A. Leaves alternate, entire or if not entire the teeth usually glandular; stipules thin, 



rUGACIOUS OR deciduous ; flowers in small umbel-like clusters "WHICH ARE RACEMOSELY 



disposed along a SIMPLE AXIS ("SIMPLE PANICLE") OR ALONG A MORE OR LESS BRANCHED 



AXIS ("COMPOUND PANICLE") ; CAPSULES OFTEN RIDGED OR CRESTED ON BACK OF 



THE LOBES OR CELLS', NEVER WITH HORNS.— Subgenus EUCEANOTHUS. 



1. Branchlets mostly flexible; spines none; bark green or brown. 

 Panicles mostly simple; flowers blue, mostly deep blue; foliage evergreen; leaves pinnately 

 nerved (except in no. 8). 

 Branch.lets terete ; leaves usually with conspicuous glandular teeth, commonly of unequal 

 size but mostly small, often thickly set on the branchlets or even crowded; panicles 

 small, often subglobose or short-oblong, frequently on long peduncles; low or 

 prostrate shrubs. 

 Leaf -margin flat, glandular-toothed. 

 Leaves dull above. 



Stems creeping; leaf -blades rounded, villous-pubescent ; panicles few (3 to 8)- 



flowered 1. C. diversifolius. 



Stems not creeping ; low flat-topped shrub ; leaf -blades elliptical to ovate, pale 

 and pubescent beneath ; panicles dense, many-flowered.. 2. C. lemmonii. 

 Leaves glossy or waxed above ; low, densely branched. 



Peduncles mostly 2 to 5 lines long ; central California near coast.. 3. C. foliosus. 



Peduncles ll^ to 2 inches long; San Diego Co 4. C. austromontanus. 



Leaf -margin revolute. 



Upper surface papillate all over; panicles oblong 5. C. papillosus. 



Upper surface papillate on margin ; panicles subglobose 6. C. dentatus. 



Branchlets angular ; leaves greener above than below ; tall shrubs or small trees. 



Leaf -blades pinnately veined, with revolute edges 7. C. parryi. 



Leaf -blades strongly 3-nerved, plane 8. C. thyrsiflorus. 



Panicles large and commonly compound (except no. 12) ; leaves mostly 3-nerved. 

 Leaf -blades serrulate, ample, prominently 3-nerved; branchlets stout. 

 Foliage evergreen, firm and thick. 



Flowers pale blue ; leaves green but dull above, whitened beneath ; small tree ; Santa 



Barbara Islands 9. C. arboreus. 



Flowers white ; leaves deep green and shining or varnished above ; mostly northern 



mountains. 10. C. velutinus. 



Foliage deciduous, thinner; flowers white; Siskiyou Co. and north 11. C. sanguineus. 



Leaf -blades entire, mostly medium or small, distinctly or obscurely 3-nerved, rarely pinnately 

 nerved ; branchlets slender ; foliage mostly deciduous. 

 Low shrub ; panicles subsimple, the peduncles short ; flowers blue ; capsule nearly crest- 

 less; leaf -blades oblong, small 12. C. parvifoUus. 



Tall shrub ; panicles compound ; flowers commonly white, sometimes blue or pinkish ; cap- 

 sule commonly with glands. 

 Leaf -blades commonly ovate, 3-nerved from the base; peduncles mostly 3 to 5 

 inches long; capsule 2 to 2% lines wide, commonly with oblong glands; 



middle altitudes in high ranges, widely distributed 13. C. integerrimus. 



Leaf -blades oblong, pinnately veined; peduncles ^2 to IV^ inches long; capsules 

 21/^ to 4 lines wide, strongly glandular-crested; high mts. of San Diego 

 Co.; Eldorado Co. foothills 14. C. pahneri. 



2. Branchlets more or less rigid and divaricate, spinose or subspinose ; bark mostly white 

 or gray; panicles mostly short-peduncled. 

 Capsules mostly crestless ; flowers white or blue. 



Branchlets with greenish or brownish bark, often angled, flexible but often with slender 



spines; leaf -blades pinnately veined 15. C. spinosus. 



Branchlets with whitish bark, terete, rigid; leaf -blades 3-nerved 16. C. leucodermis. 



Capsules crested. 



Panicles simple, commonly cylindric ; branchlets mostly rigid or stubby, not spinose, with 

 greenish or brownish bark; leaf -blades rather weakly 3-nerved, glandular-denticulate. 

 Flowers pale or whitish, sometimes deep blue. 



Leaves white beneath with a dense close felt or tomentum 17. C. tomentosus. 



Leaves mostly glabrous above, short-pubescent, pale or greenish beneath 



18. C. sorediatus. 



Flowers deep blue or purplish; leaves hirsute 19. C. oliganthus. 



Panicles compound, not cylindric ; branchlets rigid and spiny ; leaf -blades strongly 3-nerved ; 

 flowers white. 

 Low flat-topped shrub; capsule ridge-crested; leaf -blades mostly 5 to 10 lines long; 



high montane 20. C. cordulatus. 



Tall shrub; capsule conspicuously warty or wavy-ridged; leaf -blades mostly ly^ to 

 2% inches long; near coast 21. C. incanus. 



