4â LAWSON: REVISIOÎÎ' OP tltE 



places iu Sacramonlo Valley, Hurtweg- ; alkaline soil uear Livennore Pass, Brewer) ; also iu 

 Asia, and in Europe from Montpellier to St. Petersbiirg, in fields subject to standing- 

 water in winter; in England in "damp places in fields," (Bab.) " Cornfields, meadows 

 and pastures iu a gravelly soil ; the whole plant is acrid." — Withering. 



In the plant from Tsi Tsutl Mountains, the receptacle is only one-fifth of the length 

 of the peduncle, and the Vancouver Island specimens are of the same form with elongated 

 peduncle. 



Dr. Parry, in describing the North American Desert Flora, between 32' and 42 North 

 latitude (Journal of Botany, VIII., p. 343-7), gives this as the only Eanunculaceous plant of 

 these desert tracts. The annual desert plants, whose i)eriod of growth is strictly confined 

 to a short and uncertain period of spring or fall rains, require for their continued preser- 

 vation a safe deposit for their usually minute seeds during the prolonged dry season, a 

 condition which is, in great measure, supplied by the porous, sandy and gravelly soil into 

 which they fall and are safely brrried, not only out of the reach of climatic influences, but 

 also safe from the destruction of animals. Their growth is rapid and evanescent. In 

 strong contrast to these are the i^erennial plants with their thick rhizomes or tuberous or 

 tap roots, whose stores enable them to resist prolonged drought, whilst the stems and 

 foliage of others are si^ecially modified to check evaporation. Such modifications of plants 

 adapting them to resist rigorous climatic conditions are also well seen on the western 

 prairies and on the mesa or table-land around the peaks of the Eocky Mountains of the 

 South. 



The Ranunculaceœ, essentially moisture-loving plants, abound in the northern and 

 Arctic regions, and at all elevations on the mountains of the northern hemisphere where 

 there is moisture and sufficient summer heat for flowering plants. The perennial species 

 disappear on the desert, on the dry prairies, and on the driest parts of the mesa, where 

 herbaceous plants have either to give up the habit of forming thin leaf-organs or to 

 develop enormous rhizomes or roots to enable them to resist the unmitigated drought. 



2. — Myosurus aeistatus, Bentham. 



Resembling the preceding species in habit, small size, and general aspect, the leaves 

 narrowly linear, flower stalk 2 inches or more in length ; receptacle in fruit oblong or 

 linear, 2 to 8 lines long ; -Jrd the length of the stalk ; achenes xîrominently beaked, the 

 beak nearly as long as the achene. Specimens from Vancouver Island are three or four 

 inches high, nearly as large as M. minimus, birt the receptacle is more slender. The 

 beaked-achenes form the prominent character of the species. 



Myosurus aristatus. Bentham, Loud. Jour. Bot., VI., p. 458. "Watson, Bibl. Index, I., p. 

 1.5. Brewer & Watson, Bot. Calif, ed. 2, I., p. 5. Macoun, Cat., No. 26. 



M. apetalus. Gay, Hist. Chil., Bot., I., p 31, t. 1, f 1. Bâillon, Hist. PL, I., p. 43. 



Arid soil, Spence's Bridge, B.C., 19th May, ISÏô ; muddy places and on shingle, 

 Vancouver Island, B.C., 1th. May, 18*75 ; also Lytton, B.C., May 18th, 18l!i.—3Iaco?in in 

 Herb. Canad. Survey. Arid soil west of the Elbow of the South Saskatchewan, 1879 ; 

 near Reed Lake, lat. 50° 30' N. ; long. 107° 20' W.— Macoun in Cat. In the shade of sage- 

 brush, Carson and Sierra Valleys (California) to Utah ; also Chili. — B. Sj- W. 



