Euphorbiaceae. 

 EUPHORBIA L. 



Cyathium campanulate, 4 to 5 lobed, the lobes entire or slit, often hidden by glands. 

 Glands between the lobes, rarely less, entire or two horned or digitate. Male flowers: 

 numerous without calyx, very rarely w r ith a small scale on the articulation of the stamens. 

 Female flowers: single from the middle of the cyathium, finally stipitate and exserted from 

 the cyathium, naked or with a calyx formed by three small scales. Styles 3, free or 

 united, entire or bifid. Capsule separating into 3 two-valved cocci. Herbs, shrubs or 

 trees, abounding in milky juice. Leaves entire, opposite, or alternate. Cyathia in ter- 

 minal cymes or in the axis of two dichotomous branches, or in the axils of the leaves; 

 stem often thick fleshy, cactus-like or even leafless. 



The genus consists of more than 600 species, and is distributed especially 

 over the warmer regions; it is absent in the Arctic regions, and only very 

 sparingly represented in the colder parts of the temperate zone. 



In the Hawaiian Islands ten species are endemic, of which only three be- 

 come small trees. 



All Hawaiian Euphorbiae are called Akoko or Atoto by the natives. The 

 name Atoto appears also in Tahiti for Euphorbia atoto, which is called Totolu 

 and Totoyava by the Fijians. Euphorbia atoto is credited to the Hawaiian 

 Islands by Seeman, who mistook for it the closely allied Euphorbia cordata of 

 our seashores. 



KEY TO THE SPECIES. 



Leaves linear oblong; flowerheads terminal or axillary, single; capsule small. E. lorifolia 

 Leaves obovate oblong; flowerheads in open axillary cymes; capsules large. E. Rockii 



Euphorbia lorifolia (Gray) Hbd. 



Koko or Akoko. 



(Plate 100.) 



EUPHOEBIA LORIFOLIA (Gray) Hbd. Flora Haw. Isl. (1888) 395; Del Cast. 111. Fl. 

 Ins. Mar. Pacif. VII. (1892) 285. E. multiformis var. lorifolia Gray in H. Mann, 

 Proc. Am. Acad. VII. (1867) 202. E. multiformis var. angustifolia Boiss. in DC. 

 Prodr. XV. 2 (1866) 11 (ex parte). 



A small tree, with stiff branches which are nodose with short internodes and puberu- 

 lous; leaves opposite, linear or oblong, somewhat spathulate, 2.5 to 5 cm long, 4 to 10 mm 

 wide, on petioles of 1 mm or almost sessile, obtuse or truncate, often retuse at the apex, 

 entire, slightly contracted and subtruncate or uneven sided at the base, chartaceous or 

 somewhat fleshy; stipules very low, triangular with a broad base; flowerheads terminal and 

 axillary, generally single or (in the Main specimens) 2 to 3 in the leaf-axils, subsessile, 

 supported by several short bracts; involucre less than 3 mm, pubescent outside, glabrous 

 within, with 4 suborbicular glands; the lobes obovate or quadrate, with ragged margins; 

 bracteoles 3 to 4 fid; styles free to the base, shortly bifid with clavate branches; capsule 

 erect on a short stalk, 3 mm in diameter, puberulous, obtuse at the angles, the cocci 

 broader at the base; seeds rugose, scrobiculate. 



Var. gracilis Rock. var. nov. 



Branches not erect and stiff, but very slender and drooping; leaves linear oblong, 

 acute at both ends, chartaceous, opposite, on petioles of 2 to 3 mm, midrib and veins very 

 prominent, pubescent underneath, pellucid, capsules smaller, the cocci of equal width. 

 Type no. 3593 in College of Hawaii Herbarium. 



This variety is peculiar to Puuwaawaa, North Kona, Hawaii, where it grows 

 on the aa lava fields. It reaches a height of 20 to 25 feet and a diameter of 



259 



