CLASS ir, ORDER I.J PINGUICULA. 17 



tlie sun is again experienced, the hairs fall down and form a layer of 

 minute cavities above the surface, by which means evaporation is pre- 

 vented from taking place so rapidly as it otherwise would do. The 

 secretory hairs are those which have, either at the apex or base, dis- 

 tended cellules as the receptacles of secretions ; such are the glands on 

 the extremity of hairs of many of the roses, and the sac at the base of 

 the sting of the nettle, &c. 



19. V. Buxhau'mii, (Fig. 26.) Buxhauiin's Speedtvell. Stem pro- 

 cumbent, leaves petiolated cordato-ovate deeply serrated shorter 

 than the flower- stalks, segments of the calyx ovato-lanceolate 

 acute, capsule obcordate, of two tumid spreading lobes, which are 

 keeled and compressed in the upper part, cells mostly eight-seeded. 



Borrer in English Botany Supplement, t. 2769. — V. Persica, Stev. 

 — V. filiformis, Johnson's Flora of Berwick-upon-Tweed, p. 225. — 

 Hooker, British Flora, ed. 1, p. 6. — V. agresiis, ^. Hook. Br. Fl. ed. 2, 

 p. 8.— Hook. Br. Fl. ed. 3, p. 8. 



Stem from ten to eighteen inches long, procumbent, branching at 

 the base, the branches taking root. Leaves mostly alternate, inclining 

 to heart-shape, deeply serrated or inciso-serrated, shorter than the axil- 

 lary flower-stalks. Calyx segments lanceolate acute, longer than the 

 divaricated lobes of the capsule, which are keeled and compressed 

 upwards. Corolla large, bluish purple with dark veins. The whole 

 plant larger, stouter, and more hairy than V. agrestis and V. polita^ 

 for which it might be mistaken. 



Habitat. — In fields and cultivated ground ; but a doubtful native. 

 It has been found at Whiterig, Berwickshire — (Dr. Johnson), — near 

 Newcastle, Margate, in Oxfordshire, and near Glasgow, Scotland. 



Annual ; flowering during the summer months. 



GENUS III. PINGUIC'ULA. ButterworU 



Nat. Ord. Lentibula'ri.*. 



Gen. Char. Calyx permanent, two lipped, upper three cleft, the 

 lower bifid. Corolla ringent, spurred, and five cleft. Germen 

 globose. Style very short. Stigma of two unequal lobes. Cap- 

 sule one-celled. Seeds numerous, and attached to a central re- 

 ceptacle. Named from pinguis, fat; so called because the leaves 

 are greasy to the touch. 



1. P. grandiflo'ra, (Fig. 27.) large-flowered Butterwort. Spur cy- 

 lindrical, tapering, acute, the length of the yeined limb of the 

 corolla, the lower segment of which is large, spreading and notched, 

 calyx obtuse, capsule ovate. 

 English Botany, t. 2184. — English Flora, vol. i. p. 29, — Lindley, 

 Synopsis, p. 186. — Hooker, British Flora, vol. i. p. 9. 



VOL, I. D 



