GINSENG FAMILY 213 



2. Myriophyllum verticillatum L. Whorl-leaved Milfoil. Fig, 3459. 



Myriophyltiim verticillatum L. Sp. PI. 992. 1753. 



Aquatic herb, the stems simple or branched. Submerged leaves flaccid, in crowded whorls 

 of threes or fours, pinnately divided into fine capillary segments, the rachis usually flattened and 

 obviously broader than the segments; spikes 5-15 cm. long, emersed; floral leaves reduced to 

 bracts, shorter or little exceeding the flowers, ovate, acute, pectinate ; petals or the staminate 

 flowers 4, purplish, fugacious ; stamens 8 ; fruit subglobose, 2-3 mm. long. 



Ponds and quiet streams, mainly Canadian and Transition Zones; in the Pacific States ranging from Wash- 

 ington to central California, thence across the continent; also Eurasia. Type locality: Europe. May-July. 



3. Myriophyllum hippurioides Nutt. Western Milfoil. Fig. 3460. 



Myriophyllum hippurioides Nutt. ex Torr. & Gray, Fl. N. Amer. 1: 530. 1840. 



Aquatic herb, the stems simple or branching. Leaves in whorls of 4 or 5, the submerged 

 ones 15-30 mm. long, pinnately dissected into capillary segments; emersed floral leaves linear 

 to linear-lanceolate, much exceeding the flowers, pectinate or the upper entire ; petals greenish 

 white, tardily deciduous ; fruit 2 mm. long, about 1 mm. thick ; carpels flattened on the sides and 

 nearly smooth ; styles very short. 



Ponds, Upper Sonoran Zone to Canadian Zone; southern Washington to central California. Apparently most 

 abundant in the Pacific States along the lower Columbia River. Type locality: "Ponds of the Wahlamet," prob- 

 ably in the vicinity of Sauvies Island, Oregon. May-July. 



Myriophyllum elatinoides Gaudich. Ann. Sci. Nat. 5: 105. 1825. Specimens collected in the Deschutes 

 River, Oregon, are very close if not identical with this species of South America, New Zealand and Tasmania. 

 They have fugacious petals, 8 stamens; bracts 5-10 mm. long, lowest pectinate, the central serrate, and the upper 

 entire, all exceeding the flowers; fruit ovoid, carpels smooth. 



2. HIPPURIS L. Sp. PI. 4. 1753. 



Aquatic or terrestrial herbs with simple erect stems and simple entire verticillate 

 leaves. Flowers small, axillary, perfect or sometimes unisexual. Sepals minute, entire. 

 Petals none. Stamen 1, inserted on the anterior edge of the calyx. Style filiform, stig- 

 matic, its whole length along one side and lying in the groove of the anther. Fruit 1 -celled, 

 1-seeded, drupe-like. [Name from the Greek hippos, horse, and oura, tail.] 



A monotypic genus of wide geographical distribution. 



1. Hippuris vulgaris L. Mare's-tail. Fig. 3461. 



Hippuris vulgaris L. Sp. PI. 4. 1753. 



Stems simple, glabrous, 2-6 dm. high, completely submerged or more commonly emersed 

 for 10-15 cm., the base rooting at the nodes. Leaves verticillate, 6-12 in a whorl, linear or 

 lanceolate, sessile, 5-25 mm. long, 1-3 mm. wide, acute at apex; anther about 1 mm. long; 

 filament very short and stout ; fruit 2 mm. long, ellipsoid-obovoid ; stigma persistent. 



Ponds and streams, mainly Canadian and Transition Zones; Alaska to southern California on the Pacific 

 Coast, east across the continent; also Eurasia and Patagonia. Type locality: in Europe. July-Sept. 



Hippuris montana Ledeb. ex Reichb. Ic. Fl. Germ. 1: 71. pi. 86. fig. 181. 1834. Slender, 2-8 cm. high, 

 forming mats, glabrous. Leaves nl^.^■tIv 4-6. linear, sessile, 4-8 mm. long; anther 0.3 mm. _ long, much shorter 

 than the filament. Forming mats in wet alpine meadows, Hudsonian Zone; Alaska to Washington, where it has 

 been collected on Stevens Pass, Mount Baker, Mount Rainier, and the Olympic Mountains. Considered by some 

 as a form of Hippuris vulgaris L. Type locality: "Unalaschka." 



Family 108. ARALlACEAE. 

 Ginseng Family. 



Herbs, shrubs, or trees, with alternate, verticillate, or rarely opposite leaves. 

 Flowers perfect or polygamous, variously clustered. Hypanthium adnate to the 

 ovary. Sepals often minute or sometimes absent. Petals usually 5, valvate or slightly 

 imbricate, inserted on the margin of the hypanthium. Stamens as many as the 

 petals and alternate with them, rarely wanting, inserted on the epigynous disk ; fila- 

 ments filiform or short ; anthers introrse. Ovary 1- to several-celled ; styles as many 

 as the ovary cells; ovules 1 in each cell, pendulous, anatropous. Fruit a berry or 

 drupe. Seeds flattened or 3-angled, with thin testa, copious endosperm and a small 

 embryo. 



About 50 genera and 475 species, widely distributed in temperate and tropical regions. 



Leaves decompound; styles 5; our species smooth perennial herbs. 1. Aralta. 



Leaves simple, palmately lobed; styles 2; our species a spinescent shrub. 2. Oplopanax. 



