289 



ON AN APPAEENTLY ENDEMIC BRITISH 



RANUNCULUS. 



THE 



(Plate 328.) 



Ranunculus petiolaris, n. sp. — Eoot of many long white 

 fibres. Stem solitary, 9 in. to 2 ft. high, £-£■ in. in diameter near 

 the base, erect, rigid, usually more or less zigzag in outline, striate, 

 fistular, often purplish, very brittle. Original root-leaves reduced 

 to subulate petioles, rather numerous, the outer ones recurved, 

 mostly disappearing before the flowers open ; later root-leaves sub- 

 persistent, but very easily detached, erect or ascending, with or 

 without a short, blunt, linear-oblong blade, frequently 4-5 in. long; 

 lower stem-leaves similar, very erect ; uppermost linear or linear- 

 oblong, subsessile; all quite entire. Flowers few (1-4), as a rule 

 solitary, large for the plant ; sepals and fruit of R. Flammula ; petals 

 with a cuneate base, so that they appear to be distant, broadening 

 upwards to the truncate top. Whole plant quite glabrous. 



Syn. — E. Flanunida L., var. petiolaris Lange ined., Marshall in 

 Journ. Bot. 1888, 230. 



Habitat. 



W 



land. Kingshouse, Argyle!; Sligachan, Skye, E. F. d W. R. Linton, 

 sp. ; Assynt, W. Sutherland ! 



This remarkable form was first met with by myself in June, 

 1888, and by Messrs. Linton in the following August. It grows by 

 preference in water two or three inches deep, and never, so far as 

 our experience goes, occurs more than a yard or two from the 

 margin ; occupying, in fact, much the same position as Subularia 

 aquatica, with which it is associated in the original station (Lochan 

 Mathair Etive). In one instance I have seen the stem slightly 

 creeping at the base, but this was evidently exceptional and ab- 

 normal. The remarkably erect habit and peculiar leaves at once 

 attract attention, especially as the plant is usually very abundant 

 where it occurs. During the present summer I have searched for 

 it by various lakes in the east of Scotland, from Selkirkshire to 

 Ross, but without success, although in several instances the locality 

 was quite suitable. Both in Skye and Argyle it ripens fruit freely. 

 Likely to be found in Ireland. 



I have retained Prof. Lange's varietal name in a specific sense, 

 as being so thoroughly appropriate; the more readily, since he 

 himself, when determining the plant, added, "vel species nova." 



wn 



so much strengthened, that I have decided on putting it forward as 

 distinct, although it has a great deal in common with R. Flammula, 

 and many botanists may prefer to leave it as a variety or " sub- 

 species." Mr. F. J. Hanbury, to whom I showed some thousands 

 of living specimens near Kingshouse, and with whom I found it in 

 Sutherlandshire, writes : — " I am glad you are going to describe 

 Ranunculus petiolaris as a species, as I am sure it is worthy of 



Journal of Botany. — Vol. 30. [Oct. 1892.] u 



