ffypericum.] XVI. HYPERIClNEJl 81 



Ireland, but not near so frequent as H. perforatum. Pi. summer. 

 [Usually regarded as a variety of H. quadrangulum.] 



5. H. quadrangulum. Linn. (fig. 183). Square-stalked H. With 

 the general habit of the last two species, this one is readily known 

 by the four very prominent angles of the stem, and the rather smaller 

 and paler flowers. Leaves ovate, often an inch long, clasping the stem 

 at the base, with numerous pellucid nerves and dots, and a few black 

 dots round the margin on the under side. Sepals lanceolate and 

 pointed. Petals and anthers with very few black dots, or entirely 

 without them. 



In moist pastures, by hedges and ditches, in central and southern 

 Europe to the Caucasus, extending northward to southern Sweden. 

 Common in England, Ireland, and southern Scotland, but decreasing 

 in frequency towards the north. Fl. summer. H. undulatum, Schousb., 

 (H. baticum, Boiss.), found in bogs of Devonshire and Cornwall, appears 

 to be a slight variety of H. quadrangulum, with glandular sepals, 

 narrower petals, and styles only half the length of the capsule. [H. 

 quadratum, Stokes ; (tetrapterum, Fries.), is a common form or species 

 allied to quadrangulum ; it has glandular acuminate sepals, and short 

 styles.] 



6. H. humifusum, Linn. (fig. 184). Trailing ff.A. low, de- 

 cumbent, much branched, almost trailing plant, from 2 or 3 to near 

 6 inches long, sometimes forming dense spreading tufts, with a 

 perennial rootstock, but often flowering the first year, so as to appear 

 annual. Leaves of H. perforatum, but smaller. Flowers few, srnal], 

 of a pale yellow, in short, loose, leafy cymes. Sepals oblong, often 

 unequal, entire or with a few glandular teeth, and generally bordered 

 by black dots. Petals scarcely so long, with very few black dots. 

 Stamens few. 



In stony heaths, pastures, bogs, and waste places, in central Europe, 

 extending northward to southern Sweden, and carried out to some 

 other countries with European weeds ; frequent in England and 

 Ireland, less so in Scotland. Fl. summer and autumn. 



7. H. linarifolium, Vahl. (fig. 185). Flax-leaved #. Intermediate 

 in some measure between H. humifusum and //. perforatum ; taller and 

 more erect than the former, much smaller and more slender than 

 the latter, seldom above 8 or 10 inches high. Leaves linear or narrow- 

 oblong, 6 to 8 lines long, rarely marked with pellucid dots, but with 

 a few black ones underneath. Flowers in a loose corymb, larger and 

 brighter than in H. humifusum; the sepals oblong or broadly lanceolate, 

 with numerous black dots, and a few glandular teeth on the edge. 

 Petals twice or thrice as long as the sepals. Stamens not numerous. 



On dry, hilly wastes and rocky places, in western Spain, Portugal, 

 and France, extending to the Channel Islands and to Cape Cornwall, 

 in south-western England, and the Teign, in Devonshire. Fl. summer 



8. H. pulchrum, Linn. (fig. 186). Slender IT. Perennial stock, 

 shortly decumbent, the stems erect and stiff though slender, 1 to 

 near 2 feet high, with short lateral branches, all perfectly glabrous. 

 Leaves of the main stem broadly cordate and clasping the stem at the 

 base, seldom above 6 lines long, those of the lateral branches smaller 

 and much narrower, all marked with pellucid dots, but usually with- 

 out black ones. Flowers rather smaller than in If. perforatum, forming 



V 



