68 LAWSOÏT: EEVISION OF THE 



C. asarifola. DO. Syst. Nat., I., p. 309. Hook., FI. Bor.-Am., I., p. 22. Torr. & Gr., 

 H. N. A., I., p. 21. 



C. paliistris, var. asarifoKa. Eotlirock, FI. Alaska, p. 442. 



Uualasclika and Aleutian Islands. — D. Nelson, in Herb. Banks, DC. Syst. Nat. Alaska. 

 — Rothrock. Hooker, although he kept this apart as a species in Flora Bor.-Am., suspected 

 it to be too near to C. paliistris. 



3. — CAIiTHA NATANS, Pallas. 



Stem recumbent, floating, flexuous, much branched, rooting. Leaves reniform-cordate, 

 crenate, with the lobes somewhat apiiroximated, obscurely crenate near the base, toothed 

 towards the apex, the sinus deeper than in C. palustris. Flowers J inch in diameter. 

 Sepals oval. Follicles in a dense head very much shorter and broader than in palustris, 

 about \ inch in length, with a straight beak Flowers of nearly a pure white, according 

 to Sir John Eichardson, as quoted by Hooker. 



Caltha natans. Pallas, Itin. Euss., ed. Germ., III., p. 248. Forst., Trans. Linn. Soc, 

 VIII., p. 324. Pursh, Fl., II., p. 390. DC. Syst. Nat., I., p. 311. Hook., Fl. Bor.-Am., I., 

 p. 22. Torr. & Gr., Fl. N. A., I., p. 2'7. Lawson, Eanunc. Canad., p. 4.5. "Watson, Bibl. 

 Index., I., p. 8. Macoun, Cat., No. 23. 



C. palustns, var., Hook, f., Arct. PL, pp. 283 and 312. 



Creeping on the surface of deep sphaguous bogs, in the woody central districts from 

 Canada (Ontario) to lat. 60°, rare. — Richardson, Drimmond, Hook., Fl. Bor.-Am. This pro- 

 bably carries the range of the plant too far east. Flowing stream twenty miles west 

 of Edmonton, on the Lac la Nun road, N.W.T., 18*72 ; Peace Eiver tributaries, near Fort 

 St. John ; Methy Eiver, near Methy Portage, lat. bT N. — Macoun, in Herb. Canad. Survey. 

 The Amur and Ivamtschatka ; first found in Eastern Siberia by Pallas. Sir Joseph Hooker 

 (Outl. Dist. Arct. PI.) refers this as a form of C. paluslris, stating that the prevalent opin- 

 ion amongst botanists is to unite as varieties radicans and arctic.a also ; he points out that 

 this is a floating plant, affecting high latitudes only. It appears to me to be sufficiently 

 distinct, the close head of short, crowded follicles being very characteristic, as well as the 

 habit of the plant, and the form of the leaf E. Brown distinguishes natans by its capsules 

 being in a dense head, — arclica having linear anthers, — and natans, he says, has smaller 

 leaves, white flowers and oval anthers. Collectors who may meet with the living plants 

 will do well to notice these points. 



4. — Caltha leptosepala, DeCandolle. 



Eoot a fascicle of very long, straight, thick, simple fibres. Leaves radical, their 

 petioles closely aggregated and sheathing each other by the very broad, thin, membranous 

 marginal wing. Lamina elliptical-oblong, oval or heart-shaped, with acute basal sinus, 

 and more or less sagittate, nearly entire or coarsely crenate, glabrous ; first leaves smaller 

 and shorter than the later ones and with shorter petioles. Flowers, one or two from the 

 same root, but always on separate stalks ; plant never branched, as shown in Hooker's 

 figure 1 ; figure 2 shows it well. Flower 1 inch to 1^ inch across ; sepals about 8 or 9, 



