352 THE PRIMKOSE EAMILT. 



guished from other regular-flowered Monopetals by the stamens being 

 opposite to, not alternate with, the lobes of the eoroUa. This character re- 

 quires some care in observing it, especially in those species of Lysimacliia 

 which have a deeply divided, rotate corolla, and the stamens erect in the 

 centre of the flower. 

 Aquatic plant, with the leaves all submerged and pinnate, with linear 



lobes 1. HOTTONIA. 



Terrestrial plants, leaves undivided. 



Leuvps all oppntnle or ichorled. Flowers axilJary or rarely terminal. 



Stamens and divisions of the flower in fours 8. Centuncule. 



Stamens and divisions of the flower in fives. 



No corolla. Calyx pinkish 6. Glaux. 



Both calyx and cojolla. 



Capsule opening at the top. Flowers yellow 4. LvriMACHiA. 



Capsule opening transversely. Flowers blue or red ... 7. Pimpeknkl. 

 Xeaves olternufe or radical, or the upper ones irregularly whorled. 

 Flowers termiinal. 

 Leaves all radical. Flowers solitary or umbellate, on radicalpe- 

 duneles. Tube of the corolla distinct. 

 Tube of the corolla cylindrical, lobes spreadibg. No tubers . 2. Primrose. 

 Tube of the corolla nearly globular, lobes reflexed. Kootstock 



tuberous 3. Cyclamen. 



Stem leafy. 

 Leaves in one terminal whorl, with a few alternate ones below. 



Peduncles few, terminal, one-flowered. Corolla rotate . 5. Tbientale. 

 Leaves all alternate. Flowers small, white, in a terminal raceme 9. Samoi.e. 



The Dodecatheon, or American Cowslip of our gardens, belongs also to 

 the Primrose family. The allied family of Myrsinacea, mentioned above, 

 is represented in our planthouses by a species of Ardisia. 



I. HOTTONIA. HOTTONIA. 



Aquatic herbs, with submerged, pinnatiiid leaves, and flowers in whorls 

 forming a terminal raceme ; differing from Primrose in the more deeply 

 diA'ided calyx, and in the capsule, wliich opens by lateral shts instead of 

 terminal teeth. 



Besides our own species, the genus only comprises a single North Ame- 

 rican one. 



1. Water Hottonia. Hottonia palustris, Linn. 

 (Eng. Bot. t. 364. Water Violet. Featherfoil.) 



Stock perennial and creeping, with whorled leafy branches entirely sub- 

 merged ; the leaves alternate and deeply pinnatifid, with narrow-linear lobes. 

 From the centre of the whorl a single, erect, leafless flower-stem arises out 

 of the water, bearing at intervals whorls of from 3 to 5 or 6 handsome, 

 pale-purple flowers, on short pedicels, each with a small bract at its base. 

 Calyx of 5 deep, linear divisions. Corolla with a straight tube, rather 

 shorter or scarcely longer than the calyx, and a broad, 5-lobed limb. 



In pools and channels, in central and northern Europe, but not extending 

 to the Arctic Circle. Very local in western England and in Ireland, more 

 common in the central and eastern districts, and not found in Scotland. 

 Fl. early summer. 



II. PRIMROSE. PEIMULA. 



Herbs, with radical leaves ; the flowers either solitary or in a terminal 

 umbel, on leafless, radical peduncles. Calyx tubular or campanulate, with 

 5 teeth or lobes not reaching to the base. Corolla with a straight tube, and 



