CHAP. Til.] ERICE^ NORMALES. Ill 



longing to the Andromeda. In both there is 

 a honey-bearing disk under the ovary, and the 

 leaves are generally rolled in at the margin, as 

 shown at a, in Jicj. 47. 



SUB-TRIBE I.— ERICEiE NORMALES, 



All the genera in this sub-tribe, twenty-two 

 in number, were formerly included in the genus 

 Erica ; and some botanists still consider all the 

 species to belong to that genus, ^vith the ex- 

 ception of those included in Calluna, while 

 others adopt about half the new genera. In 

 this uncertainty, I shall only describe two of 

 the doubtful genera, partly because the dis- 

 tinctions between them and the true heaths are 

 strongly marked, and partly because the spe- 

 cies they contain are frequently met with in 

 British gardens^ and greenhouses, where they 

 are sometimes labelled with their old names and 

 sometimes with their new ones. 



In the genus Erica, one of the commonest 

 species is the Besom Heath (Fj. tetralix)^ which 

 is found in great abundance on moorish or boggy 

 ground in every part of Britain. In this plant, 

 the corollas of the flowers appear each to con- 

 sist of a single petal, forming an egg-shaped 

 tube (see h in Jig. 47), contracted at the mouth, 

 but afterwards spreading into a four-cleft limb, 

 through which is seen projecting the style, with 



