560 



A TEXT-BOOK OF BOTANY. 



mottled exfoliating bark. The leaves are palmately lobed and 

 within the base of the petioles are formed the winter buds. The 

 flowers are staminate and pistillate heads, borne on separate ped- 

 uncles. The fruits are spherical heads about 2 cm. in diameter, 

 composed of numerous achenes, and persist on the trees throughout 

 the winter. The wood is not only used for building purposes, but 

 also for butchers' blocks. 



FIG. 314. Cross- pollination through the agency of a bee, in flower of quince (Cy- 

 donia vmgaris). A, flowering branch; B, flower showing bee extracting nectar, and masses 

 of pollen adhering to its legs, some of which will fall upon the stigmas of other flowers when 

 it visits them ; C, ripe inferior fleshy fruit (pome) of quince. After Dodel-Port. 



/. ROSACEyE OR ROSE FAMILY. The plants are herbs, 

 shrubs or trees usually with alternate, stipulate, simple or com- 

 pound leaves, and regular perfect flowers with or without petals, 

 and numerous stamens (Fig. 280, D). The fruit is a pome (Fig. 

 314), drupe (Fig. 315), follicle or achene (Fig. 236). 



Primus scrotiiia or wild black cherry is a tree varying from 

 10 to 30 M. in height, with a more or less smooth bark marked by 

 prominent transverse lenticels, and showing a tendency to peel 

 off in semicircular pieces, which gives the older bark, which is 

 more or less black, a roughened appearance. The leaves and inner 



