MONOCOTYLEDONS AND DICOTVI.KDoNS 271 



vulus family (Convolvulacece). Allied with it are Polemo- 

 nium and Phlox (Fig. 210, b) (Polemoniacece), the gentians 

 (Gentianacece), and the dog-banes (Apocynacece) (Fig. 257). 

 It is here that the regular sympetalous flower reaches its 

 highest expression in the form of conspicuous tubes, f un- 



FIG. 256. A cluster of Rhododendron flowers. After HOOKER. 



nels (Fig. 258), trumpets, etc. The flowers are tetracyclic 

 and anisocarpic, besides being hypogynous and actinomor- 

 phic. These regular tubular forms represent about five 

 thousand species, and contain many of the best-known 

 flowers. 



