JUNIPERUS 251 



From Labrador to the Pacific (Macoun) ; southward to New Jersey and 

 Pennsylvania; westward to Michigan and western Nebraska, thence 

 southward through the Rocky Mountains to New Mexico (Britton). 



8. J. sabina, Linn. 

 Shrubby Red Cedar 



Transverse. Growth rings unequal, often coalescent on the narrower side. 

 The thin summer wood of 3-8 tracheids, rarely forming the entire 

 ring, in the broader rings becoming double or treble. Spring wood 

 open, the tracheids large and thin-walled. Resin cells not very numer- 

 ous or prominent, chiefly narrowly zonate in the spring wood, often 

 showing extensive but local aggregations when they become large, 

 rounded and loosely grouped in irregular masses with the partial 

 formation of resin canals. Medullary rays inconspicuous, distant 

 2-25, rarely 37, tracheids. 



Radial. Ray cells very sparingly resinous, chiefly straight, equal to about 

 5 spring tracheids ; the upper and lower walls thin and entire or with 

 rather distant pits ; the terminal walls thin and locally thickened or 

 coarsely pitted ; the lateral walls with rather prominent pits with a 

 broadly lenticular or oval orifice, the border rather obscure, 1-2, 

 chiefly 4, per tracheid. Bordered pits numerous, as broad as the tra- 

 cheids, generally elliptical in I compact row, the orifice large. Pits 

 on the tangential walls of the summer tracheids somewhat numerous 

 and prominent. Resin cells about 15 p. wide, 125-150 p. long. 



Tangential. Rays all narrow, the cells chiefly narrowly oval to oblong, the 

 "walls thin, variable ; when of a single cell, the latter is high, lenticular. 



A depressed, usually procumbent shrub, seldom more than 1.20 m. 

 high (Britton). 



On exposed slopes and river banks from Anticosti, Nova Scotia, New 

 Brunswick, Quebec, and Ontario, across the prairie region to the sum- 

 mit of the Rocky Mountains at Kicking Horse Pass (Macoun); from 

 Maine, westward through New York, Minnesota, and Montana (Britton). 



9. J. pachyphlaea, Torr. 



Juniper. Checkered-Barked Juniper 



Transverse. Growth rings very narrow and unequal, eccentric. Summer 

 wood dense and thin, of 2-6 tracheids, the transition to the spring 

 wood somewhat gradual. Spring wood somewhat open, the tracheids 

 in regular rows. Resin cells numerous, chiefly in the spring wood, 

 irregularly zonate. Medullary rays very prominent and resinous, i 

 cell wide, broad, distant 2-8 tracheids. 



Radial. The resinous ray cells equal to 4-13 spring tracheids; the upper 

 and lower walls medium to thick, entire or remotely pitted ; the ter- 

 minal walls strongly pitted ; the lateral walls with rather conspicuous, 

 lenticular pits about 1-2, more rarely 4, per tracheid. Bordered pits 



