Urticaceae. 



in Asia and the Indian archipelago ; about 14 per cent, in Africa, 14 per cent, in 

 Oceanic Islands and only 3 to 4 per cent, in Europe. In the Hawaiian Islands 

 the family is represented by 9 genera, of which two only are endemic (Neraudia 

 and Touchardia). Two genera, Pipturus and Urera, however, have arborescent 

 species only. The usefulness of the Urticaceae is mainly in the long and very 

 strong fiber which is obtained from the bark of some species. The fibre of the 

 Hawaiian Olona (Touchardia latifolia) is one of the strongest in the world. 



KEY TO THE GENEEA. 



Urereae. Perigone of the female flowers four parted or four lobed. 

 Flowers in cymes. 



Cymes divaricately dichotomous, corymbose, achene covered by the fleshy 



perigone 1. Urera 



Boehmerieae. Perigone of the female flowers tubular, free. 

 Flowers in axillary clusters. 



Female flowers on a globose receptacle, the perigone dry with fruit . 2. Pipturus 



URERA Gaud. 



Perigone of the male flower 4-5 parted, stamens 4-5, and a globose or cupshaped rudi- 

 mentary ovary. Female flower with equally large, or smaller outer segments. Stigma 

 globose-penicillate or cylindrical, subsessile. Achenes enclosed in the fleshy perigone. 

 Seeds with scanty albumen. Trees or shrubs with alternate leaves, and punctiformous to 

 elongate, in the Hawaiian species ovate-elongate cystolithes, flowers in dichotomous or 

 irregiUarly branching, loose cymes or corymbs. 



The genus Urera consists of about 22 species distributed over the tropics of 

 America and Africa and the islands of the Pacific. In the Hawaiian Islands we 

 have only two species with several varieties, both species being peculiar to the 

 islands, outside of which they have not been found. The native name for both 

 species is Opuhe. 



Urera Sandvicensis Wedd. 



Opuhe. 

 (Plates 38, 39, 40.) 



URERA SANDVICENSIS Wedd. in Ann. Sci. Nat. ser. 3. XVIII (1852) 177, et in DC. 

 Prodr. XVI (1869) Sect. I. 92; H. Mann Proc. Am. Acad. VII (1867) 200; 

 Hbd. Fl. Haw. Isl. (1888) 410 inclus. var. .; Del Cast. 111. Fl. Ins. Mar. Pac. 

 VII (1892) 299. Villebrunea crenulata Gaud. Bot. Voy. Bonite (1844-52) t. 92. 



Leaves oblong, 15 to 20 cm x 7 to 9 cm, on petioles of 3 to 5 cm, acuminate, moderately 

 elliptico-contracting but more or less obtuse at the base, wavy crenulate in the upper, 

 entire in the lower portion, chartaceous, or thick somewhat fleshy, pale underneath, either 

 glabrous or pubescent along the veins and midrib, veins impressed in fresh specimens, 

 penninerved, with 12 to 15 strong nerves on either side, all parallel, straight, the lowest 

 equally long or often longer (not shortest as given in Hillebrand 's Flora); stipules lanceo- 

 late about 4 cm; flowers dioecious; cymes in the lower axils, often rising from the naked 

 branch, regularly and repeatedly dichotomous, corymbiform, 5 to 8 cm in diam. with a 

 peduncle of about 15 mm'in the female and 30 to 35 mm in the male flowers; male perigones 

 8 to 20 in a glomerule, subsessile, each about 3 mm in diam., pale reddish or yellow, with 

 4 to 5 segments; anthers pale usually 5 in number; female perigone surrounded by a 

 deciduous cup of bractlets, shortly pedicellate, 3 to 4 toothed, at length fleshy and orange 

 yellow, about 2 mm or less; achene suboblique, with yellow stigma, ovate, tuberculate 

 on both faces, entirely enclosed by the perigone. 



119 



