A SYSTEMATIC STUDY 



OF THE 



SPECIES WHOSE WOODS ARE REPRESENTED IN THE ACCOMPANYING 



SECTIONS. 



CLASS ANGIOSPERNLS: 



All trees, excepting the tree ferns of tropical regions, belong to the 

 division of the vegetable kingdom known as Spermatophyta, i. e., they 

 produce seeds. 



This group is subdivided into Angiosperma-e and Gymnospermae, 

 both of which are represented in our arborescent flora, and are sub- 

 divided in turn into orders, genera, etc. The Angiospermae include all 

 plants producing flowers in which the seed is developed in a closed 

 ovary. Such of the orders as we have to do with here will be defined 

 in the following pages. 



ORDER MORACE^: MULBERRY FAMILY. 



Leaves conduplicatc or involute in the bud, petiolate, alternate, deciduous, 

 with caducous stipules inclosing the leaf in the bud. Flowers monoecious or 

 dioecious, small, in ament-like spikes or heads, from the axils of caducous bud- 

 scales or of the lower leaves of the shoots of the season; calyx 3-5-lobed or 

 parted; corolla none; stamens I to 4, inserted at the bases of the calyx-lobes; 

 ovary superior, i-2-celled; styles 1-2; ovules solitary, anatropous and pendulous. 

 Fruit an aggregation of drupelets, each inclosed in the thick fleshy calyx. 



Trees, shrubs and herbs of over nine hundred species, generally with 

 milky juice and natives of temperate and tropical regions. They are 

 grouped in fifty-four genera, of which four are represented in North 

 American trees, three being indigenous and the fourth a naturalized 

 species. 



