CLASSIFICATION OF DICOTYLEDONS. 



211 



racece. The heath family (Ericaceae), besides the true heaths 

 (Erica, Calluna), includes the pretty trailing-arbutus or may- 

 flower (Epigcea), Andromeda, Oxydendram (Fig. 116, E), 

 wintergreeii (Gaultheria), etc. The last family is represented 

 by the cranberry (Vaccinium) and huckleberry (Gaylussacia) . 



FIG. 116. Types of Isocarpous sympetalse (Bicornes). A, flowers, fruit, and 

 leaves of huckleberry, Gaylussacia (Vacciniess) , x 1. B, vertical section of 

 the flower, x 3. (7, a stamen : i, from in front ; ii, from the side, x 4. D, 

 cross-section of the young fruit, x 2. E, flower of sorrel-tree, Oxydendrum 

 (Ericacese), x 2. F, flower of azalea (Rhododendron), x %. G, cross-section 

 of the ovary, x 3. 11, diagram of the flower. /, flower of mountain laurel 

 (Kalmia), x 1. J, prince's-pine, Chimaphila (Pyrolacese) , x y 2 . K, a single 

 flower, x 1. L, plant of pine-sap, Monotropa, (Monot ropeds) , x l / 2 . M, section 

 of a flower, x 1. 



The second order, the primroses (Primulince), is principally 

 represented in the cooler parts of the world by the true prim- 

 rose family (Primulacece), of which several familiar plants may 

 be mentioned. The genus Primula includes the European 

 primrose and cowslip, as well as two or three small American 

 species, and the commonly cultivated Chinese primrose. Other 



