PLATE XII 



Ribes hudsonianum (25a and 25b) 



Vessels present; vessels mostly solitary with some small 

 clusters of vessels; these vessels or clusters are randomly 

 dispersed with no clear pattern evident; growth ring not ini- 

 tiated with a band of larger vessels although the vessels of 

 the last -formed wood are noticeably smaller than the initial 

 vessels, making the growth rings discernible; perforation 

 plates scalariform; rays three to many cells in width, often 

 massive, dispersed between uniseriate rays. 



Ribes irriguum (26a and 26b) 



Vessels present; vessels may be diagonally alined, in 

 short tangential bands, and/or diffuse, with none of these 

 found exclusively; perforation plate scalariform; rays three 

 to many cells in width, often massive, dispersed between 

 uniseriate rays. 



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