270 OHIO STATE ACADEMY OF SCIENCE. 



16. Primaries ascending a long way near the margin, usu- 

 ally not arching; leaves narrow, often auriculate 

 in rank growth. 5. longipes. 



16. Primaries more distant, forming a series of arches or 

 loops near the margin; not auriculate. 17. 

 17. Leaves ovate; northern. S. adenophylla. 



17. Leaves lanceolate. 5. cordata. 



18. Leaves green on both sides, only a little paler if at all 



beneath. 19. 

 18. Leaves glaucous beneath. 27. 

 19. Leaves relatively thin, dull. 20. 



19. Leaves subcoriaceous, glossy above, strongly glandular es- 

 pecially on the stipules, ovate or broadly lanceolate, 

 often, especially in rank growth, very long attenuate; 

 buds and twigs bright shining brown, buds large; a 

 beautiful shining shrub ; northern. 5. lucida. 



20. Marginal vein prominent, extending nearly to the base 



of the leaf, primaries distant. 21. 

 20. Marginal not present, primaries closer. 23. 

 21. Leaves very finely serrate, reticulate venation very fine, 

 long acuminate, frequently falcate ; growing into a scrag- 

 ly tree, along streams. 5. nigra. 



21. Leaves spinulose serrate to entire, teeth rather distant, 

 meshes coarse, acute, not falcate; shrubs tending to 

 form close thickets. 22. 

 22. Leaves, except those at the bases of the season's twigs, 

 less than 1 cm. wide. 5. interior. 



22. Leaves more than 1 cm. wide. 5. interior ivheeleri 



23. Leaves dark purple green, entire or obscurely serrate. 24. 

 23. Leaves bright green, mostly distinctly serrate. 25. 



24. Leaves elliptical; dwarf shrub in sphagnum bogs only. 



5. pedicellaris . 

 24. Leaves mostly oblanceolate ; shrub with many ascend- 

 ing branches, often planted. S. purpurea. 

 25. Venation irregular, primaries mostly arching or looping; 



shrubs. 26. 



25. Venation regular, primaries ascending to near the margin ; 



arborescent; water-shoots of 5. fragilis. 



26. Leaves sharply serrate; shrub with branches lopping 



over onto the ground. 5. cordata. 



26. Leaves distantly serrate with incurved teeth; shrub 



with stems ascending. 5. discolor. 



27. Leaves spatulate, elliptical, or oblong-oblanceolate, not 



sharply serrate. 28. 

 27. Leaves lanceolate or broader than above, serrate. 31. 



