SUMMARY Z21 



It happens that the number of species of trees, large and 

 small, in Alabama is just about the same as in most other south- 

 eastern states (except Florida, which has more, on acccnint of 

 the large tropical element in the extreme south), and also Texas 

 and California, which are much larger and more diversified. Of 

 course the number enumerated could be greatly increased by in- 

 cluding the multitude of doubtfully distinct forms of Crataegus, 

 Tilia, etc.. but the same could be done also in other states, and the 

 relative numbers would still be about the same. Incidentally we 

 have considerably more species of trees than the whole of lui- 

 rope. Data on numbers of species of shrubs and vines in other 

 states and countries are not readily available, but they are probably 

 approximately jiroportional to the trees, in climates like ours. 



The family represented by the most genera of woody plants 

 is Ericaceae, with T. Large trees are most numerous in the Cupu- 

 liferae (mostly oaks), small trees (not counting Crataegus) like- 

 wise, vines in the Vitaceae (unless we should split the species of 

 Sinilax more minutely), and shrubs in the Ericaceae. It is in- 

 teresting, and perhaps of some evolutionary significance, that all 

 our Gymnosperms are large trees, about half the large trees are in 

 the group Apetalae, and most of the small trees, vines and shrubs 

 in the Polypetalae. The Gamopetalae have comparatively few 

 woody plants in proportion to the total number of species in that 

 group. 



It is a curious fact that in some families which consist mostly 

 of herbs, such as Polygonaceae, Labiatae, Solanaceae, Ambros- 

 iaceae and Compositae, our shrubby representatives are chiefly 

 confined to the vicinity of the coast. It happens that these all 

 have simple leaves ; while in two other mainly herbaceous families, 

 the Ranunculaceae and Araliaceae, our single woody representa- 

 tives have compound leaves and show no partiality to the coast. 



