RHAMNACE.E 7 C 29 



spicuously 3-nerved, irregularly serrate with incurved apiculate teeth, or coarsely dentate, 

 and often 1|' long and f ' wide; stipules minute, acute. Flowers light or dark blue, very 

 fragrant, opening from March until May, in lax corymbs from the axils of acute pubescent 

 red caducous bracts on upper leafy branchlets of the year, the whole inflorescence forming 

 an open thyrsus often 5'-6' long and 3'-4' thick, leafless toward the apex. Fruit depressed, 

 obscurely lobed, crestless, black, \'-\' in diameter. 



A tree, 18-20 high, with a trunk o'-6' in diameter, upright branches forming a narrow 

 open head, and slender divaricate angled branchlets pubescent or puberulous when they 

 first appear, soon glabrous, bright green, ultimately reddish brown, frequently terminating 

 in sharp leafless thorn-like points; more often shrubby. Bark of the trunk thin, red-brown, 

 roughened by small closely appressed scales. 



Distribution. California, common in mountain canons near the coast of Santa Barbara, 

 Ventura, and Los Angeles Counties; often forming a dense undergrowth in the forest, which 

 it enlivens for many weeks in early spring by its large clusters of bright blue flowers. 



6. COLUBRINA Brong. 



Trees or shrubs, with terete branches and scaly buds. Leaves alternate, petiolate, 

 pinnately veined or triple-veined from the base, often ferrugineo-tomentose on the lower 

 surface, persistent. Flowers axillary, in contracted few-flow r ered cymes or fascicles, 

 yellow or greenish yellow; calyx-tube hemispheric, persistent, 5-lobed, the lobes spread- 

 ing, triangular-ovate, keeled on the inner surface, deciduous by a circum.scissile line; 

 disk fleshy, annular, 5-angled or indistinctly 5 or 10-lobed ; petals 5 yellow or white, 

 inserted under the margin of the disk, shorter than the lobes of the calyx, cucullate, 

 unguiculate, infolding the stamens; stamens 5, opposite to and inserted with the petals; 

 filaments incurved; anthers ovoid; ovary surrounded by and confluent with the disk, 

 3-celled, subglobose, contracted into a slender 3-lobed style, the obtuse lobes stigmatic on 

 the inner face; ovule erect, from the base of the cell. Fruit subglobose, 3-lobed, the outer 

 coat thin and septicidally dehiscent into 3 1-seeded crustaceous nutlets 2-valved at apex. 

 Seeds erect, broad-obovoid, compressed, 3-angled; seed-coat coriaceous, smooth and shin- 

 ing; embryo axile in thick fleshy albumen; cotyledons orbicular, flat or incurved, thin or 

 fleshy. 



Colubrina with about a dozen species is confined to the tropics, with the largest number 

 of species in the New World. Of the four species found within the territory of the United 

 States three are arborescent. 



The generic name is from coluber, a serpent, probably on account of the peculiar twisting 

 of the deep furrows on the stems of some of the species. 



CONSPECTUS OF THE ARBORESCENT SPECIES OF THE UNITED STATES. 



Leaves thin, elliptic, ovate or lanceolate, glabrous at maturity. 1. C. reclinata (D). 



Leaves thick or coriaceous. 



Leaves oblong to elliptic, rounded or acute at apex, densely soft-pubescent. 



2. C. cubensis (D). 



Leaves elliptic to ovate-lanceolate, bluntly pointed at apex, coriaceous, rusty-pubescent 

 beneath. 3. C. arborescens (D). 



1. Colubrina reclinata Brong. Naked Wood. 



Leaves elliptic, ovate or lanceolate, usually contracted at apex into a blunt point, 

 cuneate or somewhat rounded and furnished with 2 conspicuous marginal glands at base, 

 and entire when they unfold in early summer thin, glabrous or finely puberulent below 

 and along the principal veins, and at maturity thin, yellow-green, 2|'-3' long and 1^' to 

 nearly 2' wide, with a stout midrib and arcuate primary veins; persistent until their second 

 year; petioles slender, ' in length. Flowers in cymes rather shorter than the petioles, on 

 shoots of the year, pubescent, soon becoming glabrate. Fruit \' in diameter and dark 

 orange-red, ripening late in the autumn, on pedicels \' in length: seeds light red-brown, 

 f'long. 



