104 Proceedings of the Ohio State Academy of Science 



c. Cones erect. Abies. (6). 



d. Leaves more or less 4-angled or tetragonal, sessile. 



Picea. (4). 

 d. Leaves flat, short-petioled. Tsuga. (5). 

 3. Leaf buds naked ; carpels few, spiral ; leaves on feather-like 

 dwarf branches which are deciduous. Taxodiaceae. 



a. Taxodium. (7). 



3. Leaf-buds naked ; carpels few, opposite, sometimes forming 



a black or blue berry-like fruit; leaves opposite or 

 whorled, rarely scattered, persistent. Juniperaceae. 

 a. Cones oblong, ovuliferous scales not peltate. 



Thuja. (8). 

 a. Cones globose, ovuliferous scales peltate. Chamae- 



cyparis. (9) . 

 a. Cones becoming fleshy, berry-like. Juniperus. (10). 



4. ANGIOSPERMAE. 



4. Leaves mostly parallel-veined, sometimes netted-veined ; 



parts of the flower very often in threes (trimerous) ; 

 cotyledon i ; vascular bundles scattered through the pith, 

 usually not in a circle ; no annual rings of growth. No 

 trees in our region. Monocotylae. 



4. Leaves usually netted-veined ; parts of the flower more com- 



monly in fives (pentamerous) or fours (tetramerous) ; 

 cotyledons usually 2 ; vascular bundles usually in a circle 

 around a central pith, forming annual rings of growth 

 in perennial stems, with bark on the outside. 5. 



5. DICOTYLAE. 



5. Perianth none or of similar segments or divided into calyx 



and corolla; corolla when present choripetalous (petals 

 distinct). 6. 

 5. Perianth composed of calyx and corolla, calyx may be min- 

 ute or suppressed; corolla sympetalous (petals more or 

 less united). 36. 



