200 



SYSTEMATIC BOTANY. 



of our common weeds belong to this family, as Mullein 

 {yerbaseimi), Toad-Flax {Linaria), 

 Lousewort (^Pedicrularis), etc. 



6. Solanaceae, The Night- 

 shade family comprises from twelve 

 hundred to fifteen hundred species, 

 found chiefly in the Tropics. The 

 plants have often a suspicious look, 

 and contain a poisonous principle. 

 The flowers are five-merous and regular (Fig. 312), and 

 the fruit is a two-celled pod or berry. The Potato (Solar 

 num tuberosum) is a native of America, from Mexico to 

 Chili ; but in its wild state the tubers are very small. By 

 culture and selection, for two or three hundred years, they 

 have been enormously increased- (Fig. 313), and are now 

 cultivated in nearly all countries. The cells of the tubers 

 are filled with large, oval starch grains (Fig. 348). The 

 Egg-plant (S. Melongena?), cultivated for its edible fruit, is 

 a native of South 

 America. For its 

 wholesome fruit, the 

 Tomato (Lycoperd- 

 eum esculmitum), a 

 native also of South 

 America, is generally 

 cultivated in warm 

 and temperate coun- 

 tries. Belladonna is 

 obtained from the ^i^ 



Deadly Nightshade (Atropa Belladonna), a plant of the 



Fig. 312. Rotate corolla of the Potato-plant. Fig. 31S. Potato Tubers; it, Stem; 

 f, soil ; r, roots. 



