CLASSIFICATION OF DICOTYLEDONS. 195 



attempting to get out, the smooth, slippery wall at the bottom, 

 and the stiff, downward-directed hairs above, prevent their 

 escape, and they fall into the fluid which fills the bottom of 

 the cup and are drowned, the leaf absorbing the nitrogenous 

 compounds given off during the process of decomposition. 

 There are other species common in the southern states, and a 

 California pitcher-plant (Darlingtonia) has a colored appendage 

 at the mouth of the pitcher which serves to lure insects into 

 the trap. 



Another family of pitcher-plants (Nepenthece) is found in 

 the warmer parts of the old world, and some of them are 

 occasionally cultivated in greenhouses. In these the pitchers 

 are borne at the tips of the leaves attached to a long tendril. 



Two other families of the order contain familiar native 

 plants, the rock-rose family (Cistacece), and the St. John's- 

 worts (Hypericacece) . The latter particularly are common 

 plants, with numerous showy yellow flowers, the petals usually 

 marked with black specks, and the leaves having clear dots 

 scattered through them. The stamens are numerous, and often 

 in several distinct groups (Fig. 105, (7, D). 



The last order of the Aphanocydce (the Columniferce) has 

 three families, of which two, the mallows (Malvacece), and the 

 lindens (Tiliacece), include well-known species. Of the former, 

 the various species of mallows (Fig. 106, A) belonging to the 

 genus Malva are common, as well as some species of Hibiscus, 

 including the showy swamp Hibiscus or rose-mallow (H. mos- 

 cheutos), common in salt marshes and in the fresh-water 

 marshes of the great lake region. The hollyhock and shrubby 

 Althcea are familiar cultivated plants of this order, and the 

 cotton-plant (Gfossypium) also belongs here. In all of these 

 the stamens are much branched, and united into a tube enclos- 

 ing the style. Most of them are characterized also by the 

 development of great quantities of a mucilaginous matter 

 within their tissues. 



The common basswood ( Tilia) is the commonest representa- 



