MONOCOTYLEDONS AND DICOTYLEDONS 235 



is said to be pinnate or pinnately veined, and inclines to 

 elongated forms. In the other case several ribs of equal 

 prominence enter the blade and diverge through it (Fig. 

 218). Such a leaf is palmate or palmately veined, and in- 

 clines to broad forms. 



(4) Cyclic flowers pentamerous or tetramerous. The 

 flowers " in fives " are greatly in the majority, but some 



FIG. 218. Leaves showing pinnate and palmate branching; the one to the left is from 

 sumach, that to the right from buckeye. CALDWELL. 



very prominent families have flowers "in fours." There 

 are also dicotyledonous families with flowers "in threes," 

 and some with flowers "in twos." 



It should be remembered that no one of the above char- 

 acters, unless it be the character of the embryo, should be 

 depended upon absolutely to distinguish these two groups. 



