622 PATAGONIAN EXPEDITIONS : BOTANY. 



i. HYDROCOTYLE Linn. 



Prostrate marsh herbs, with palmately nerved or lobed or peltate leaves, 

 mostly broad, on long petioles, with scale-like stipules; and small, white 

 flowers in simple, sessile or peduncled umbels, with a small involucre. 



Species 100, cosmopolitan. (Fig. in Eng. & Prantl, iii, 8, p. 117.) 



KEY TO THE SPECIES. 

 A. Leaves peltate. 

 b. Leaves orbicular. 



c. Umbel 2O~3O-flowered. umbellate. 



C2. Scape umbelled and flowers whorled along its branches. bonariensis. 



b2. Leaves subreniform. Rays many. modesta. 



Az. Leaves- subpeltate, nearly single at the nodes. Umbels 3-5-flowered. batrachioides. 



AT,. Leaves not peltate. 



b. Leaves round-cordate, /-lobed. Flowers about 25. araucana. 



bz. Leaves round-reniform, 5 -lobed. Umbels 5- 1 2-flowered. ranunculoides. 



b$. Leaves reniform. Umbel 10-12 -flowered. bonplandi. 



I. H. ARAUCANA Phil. 



Stem erect, simple, slender, few-leaved, covered with long hairs ; as 

 are the petioles, etc. Leaves glabrous, orbicular, cordate, y-lobed, crenate. 

 Pedimcles shorter than petioles ; flowers 25, subsessile. Fruit small. 

 Araucaria and Valdivia. 



H. ARAUCANA PATAGONICA Speg. 



Stems creeping ; and all the plant glabrous. 



2. H. BATRACHIOIDES DC. 



Glabrous. Leaves nearly single at the rooting nodes, long-petioled, 

 erect, subpeltate, 3-5-partite, the parts ciineate, obtuse, 2-4-cleft ; lobes 

 entire or subcrenate. Peduncles scarcely 25 mm. long, deflexed in fruit. 

 Umbels 3-5-flowered. Flowers subsessile. 



(Chili) ; N. Patagon., by Rio Negro. 



3. H. BONARIENSIS Lam. (H. umbellata bonariensis.] 

 Glabrous. Leaves peltate, orbiculate, i5-2O-nerved, bicrenate. Scape 



scarcely longer than the petioles, apically umbelled and further branching. 



Flowers whorled along the branches. 



(Argentina) ; N. Patagon., by Rio Negro, along damp maritime regions. 



Multiform. 



