PRIMROSE TRIBE. 471 



a. Ovary 1-celled. 



Seeds numerous, placentae parietal Cucurbitaceee, 606 



Seeds single Fruit dry . . Composites, 629 



Fruit succulent . . . Loranthece, 621 



8, Ovary 2 or more-celled. 



Leaves opposite . . . Caprifoliacece, 623 

 Leaves verticillate (in all the 



British species) . . . Rubiacea, 624 



Leaves alternate . . . Cantpanulacece, 637 



Ovary superior Ericinece, 640 



SUB-CLASS III. COROLLIFLOR^E. 



644. The members of this division are easily distinguished 

 from the foregoing, by attention to the following particulars. 

 The calyx and corolla are each formed in one piece, that is, 

 the sepals and petals are adherent at their edges ; but they are 

 quite distinct from each other, and from the ovarium, which is 

 consequently always superior (save in a few exceptions). The 

 stamens are adherent to the base of the corolla, and, as it were, 

 inserted into it. The only one of the foregoing orders to which 

 these characters apply, is the Heath tribe, which connects the 

 preceding sub-class with this one, serving as an illustration of 

 the general principle formerly mentioned, that, in any Natural 

 arrangment, such links must occur, the true place of which may 

 be doubtful. 



645. The first order in this sub-class, although of small im- 

 portance, may yet be briefly noticed, because every one is familiar 

 with some species of it, which will serve as an illustration of the 

 general structure of the group. This is the order PRIMULACKE, 

 or Primrose tribe, the flowers of which are easily described. 

 The Calyx is formed of one piece, cleft most commonly into five 

 teeth, however, at the edges, indicating that it is composed of 

 five adherent sepals ; and a division of the same sort presents 

 itself in the corolla, which has generally a rather long tube. 

 On drawing away the latter, in the common Primrose, Cowslip, 

 or Polyanthus, the stamens will come away with it ; and on 

 counting them, it will be found that they are equal in number to 

 the divisions of the corolla, but are opposite to them, indicating 



