KEY TO THE SPECIES OF HEMLOCKS 



Needles flat, obtuse, grooved above, with 2 whitish bands below; 

 cones light brown, small {Vi-^Vi inches long), ovoid. 

 2. Needle margin finely toothed; needles mostly 2-ranked; cones 

 J/2~l inch long. 



3. Needles tapering from base to apex, with well defined, 

 narrow white bands below; cones stalked, Vi-% inch long, 

 oblong-ovoid, with scale margins smooth; buds ovoid, 

 pointed; eastern. ... 7". canadensis, Eastern Hemlock, p. 67. 

 3. Needles of uniform width from base to apex, with poorly 

 defined bands below; cones sessile; %.-l inch long, ovoid, 



with scale margins undulate ; buds globose ; western 



T. heterophylla, Western Hemlock, p. 69. 



2. Needle margin entire; needles spreading in all directions; cones 



1-1 V^ inches long; Appalachian Mountains 



T. caroliniana, Carolina Hemlock, p. 67. 



Needles rounded or keeled above, stomatiferous on all surfaces, 

 spreading in all directions; bluntly pointed; cones yellow-green 

 to purple, %-3^ inches long (mostly about 2 inches long), 

 oblong-cylindric T. mertensiana, Mountain Hemlock, p. 71. 



[65J 



