1918] RECORD—RESINOUS TRACHEIDS 63 
gymnosperms resinous tracheids are almost exclusively confined to Dammara 
and Araucaria, though it is a noteworthy fact that similar structures occur 
rarely among the higher Coniferales..... The taxonomic value of the 
Fic. 2 
API. 
Fics. 2, 3.—Fig. 2, radial section; fig. 3, tangential section of Pinus albicaulis 
resinous tracheids applies exclusively to the Cordaitales, where they are of 
ordinal value, though in Dammara and Araucaria they may also become ot 
specific value. 
