NOTES ON CAREX FLAVA AND ITS ALLIES 



II— CAREX LEPIDOCARPA IN THE BRITISH ISLES* 

 By Elizabeth W. Davies 



University College of Leicester 



Carex lepidocarpa grows in isolated and scattered areas throughout the country, 

 wherever suitable localities occur. It shows considerable variation in form and size 

 over its range, but this can usually be correlated with its different habitats, and its regional 

 adaptation to climate and topography. In fact this species seems to form a discontinuous 

 topocline in the British Isles (Huxley, 1939) and the character gradient in this case is 

 clearly associated with latitude and altitude. Thus the southern lowland and Scottish 

 mountain plants represent the extreme forms. The former, confined to the fens and 

 calcareous marshes in southern England, is very different from the latter, a plant of 

 base-rich flushes on high mountains, and these forms remain distinct even in cultiva- 

 tion. However, as some populations in the Midlands and northern England (the carboni- 

 ferous limestone of the Pennines, in Derbyshire, Yorkshire, Durham and Westmorland) 

 show intermediate characters and are difficult to classify, it seems best to regard these 

 extreme forms as subspecies. A short description of the species and the two subspecies 

 found in the British Isles now follov/s. 



C. LEPIDOCARPA Tausch, 1834, Flora, 17, 179. C. flava L. sec. Host, 1801, Gram, 

 Aust., 1, t. 63, (pi. florifera), non L. 



A tufted glabrous perennial (20-) 30-50 (-60) cm. high, generally smaller and more 

 slender in all its parts than C. flava L. Stems stout and erect, or slender and slightly 

 pendulous. Leaves (1-5-) 2-2-5 (-4) mm. wide, usually about half the length of the 

 stems or less; ligule c. 1 mm., truncate or nearly so. Lower sheaths green, som_etimes 

 becoming brown and fibrous. Male glumes 3-3-5 mm., obovate or obovate-lanceolate, 

 brownish-hyaline, midribs green or brown, not distinctly keeled. Female spikes 1-3 (-4), 

 8-12 X 5-7 mm., rarely contiguous, often somewhat distant, sessile, or lower shortly 

 peduncled. Bracts leaf-like, slender, equalling or sometimes exceeding the inflorescence. 

 Female glumes 2 mm., ovate, acute, dark brown or yellow-hyaline. Perigynia (3-5-) 

 4-25-4-5 (-5-0) mm., obovoid-trigonous, narrowed gradually into a beak, allb ut the upper 

 arcuate-deflexcd when ripe; beak 1-5 mm., attenuate, serrulate. Nuts 1-5 mm., broadly 

 obovoid-trigonous or almost round. Fl. 5-7. Fr. 7-9. 



(1) C. LEPIDOCARPA Tausch subsp. LEPIDOCARPA. Plate 6a. 



I have not seen Tausch' s type from Bohemia. Tausch, however, refers to Host's 

 plate (see above), and suggests that it is similar to his own plant. This plant resembles 

 the lowland form of C. lepidocarpa in every way. I have, therefore, assumed that Tausch's 

 plant is the same subspecies. 



A tufted perennial (20-) 30-50 (-60) cm. Stems slender and often curved when in 

 fruit. Leaves 1-5-2-5 (-3-5) mm. wide, herbaceous, usually about half the length of the 

 stems. Female glumes pale brown-yellow, hyaline, caducous. Perigynia (3-5-) 4-25-4-5 

 (-4-75) mm. (Fig. 3). Fl. 5-6. Fr. 7-8. 2n - 68. 



• Tail ol a thc^io appiovcJ lui the degree ul I'b.U. by the Univcibity of London. 



70 



