xv] 



ROSACEOUS TYPE 



145 



are zygomorphic in the median plane. In some of the 

 flowers, however, this plane of zygomorphy may be 

 oblique. 



5" 



Fig. 42. Flower of the Sycamore, showing, 2, complete flower ; 3, the 

 same after removal of petals and sepals, the stamens arising from the 

 fleshy disc ; 4, staminate flower seen from above ; 5, ovary with the 

 hypogynous disc; 6, ovary in transverse section (Wi). 



The typical floral formula is therefore : 

 K s G s A i+t ff(2) 



with median or oblique symmetry of the androecium and 

 pistil. 



A well-marked type is the Rosaceous flower, charac- 

 teristic, as its name denotes, of the large family Rosacese 

 to which the Roses, Blackberry, Raspberry, Apple, Pear, 

 Hawthorn, Rowan, Service-tree and other species of 

 Pyrus, and the Cherry, Plum, and other species of Prunus 

 belong (Fig. 43). 



The Rosaceous flower has a more or less well-defined 

 calyx-tube, or hollowed receptacle, which may be shallow 



w. HI. 10 



