202 FAMILIES OF FLOWERING PLANTS 
Fig. 176. Hemlock Water-parsnip (Sium cicutaefolium). After Britt & Brown, 
Ill. Fl. Northern U. S. 
surrounded by an involucre. They are most abundant in the northern 
hemisphere, North America possessing 3 genera and about 35 species. 
Of these, the best known and most abundant is Cornus, including the 
dogwoods or cornels. About 18 species are found in this country, the 
Fig. 177. Dwarf Cornel (Cornus Canadensis). After Britt & Brown, Ill. Fi. 
Northern U. S. 
most conspicuous being the flowering dogwood (0. florida). A common 
species of low, cold northern woods is the little bunch berry (C. 
