ANALYTICAL KEY. 



71 



additional NOTES— continued. 



The various species of elm may be distinguished as follows : 



1 Pores of spring wood form a broad baud of several rows; easy splitting, 



"dark brown heart (No. 64) Bed ELM. 



2. Pores of spring wood usually in a single row, or nearly so. 



a. Pores of spring wood large, conspicuously so (No. 62) WHITE ELM. 



b. Pores of spring wood small to minute. 



a'. Lines of pores in summer wood fine, not as wide as the intermediate 



spaces, giving rise to very compact grain (No. 03) Rock elm. 



}>'. Lines of pores broad, commonly as wide as the intermediate spaces, 



(No. 66) Winged elm. 



c Pores in spring wood indistinct, and therefore hardly a ring-porous 



\ vood (No. 65) Cedar elm. 



Fig. 47—Wood of elm. a, red elm ; 6, white elm ; c, winged elm. 



i su.w. 



} sp.w. 



Yh:. IS.— Walnut, p. r., pith rays; c. I,, con 

 centric lines; v, vessels or pores; su. w. 

 summer wood: sp. to., spring wood. 



Fig. 49.— Wood of cherry. 



