32 ANDERSON: DASYSCYPHA RESINARIA CAUSING 
The canals of the chains are separated only by one or two 
medullary rays and very few tracheids are formed in the zone of 
the resin canal chain. The lining cells of the canals are of paren- 
chymatic origin, shown by the numerous simple pits present in 
their walls. Wound parenchyma cells are always present in the 
canal zone. These cells are thick-walled and simple pitted and 
are best seen in tangential sections (jig. 77). 
The lumina of many of the canal lining-cells are filled with 
hardened resin. The same is true also of many of the tracheids 
surrounding the canals. These “resin-cells” (figs. 9 and 10), 
are also present in the normal wood of Adzes balsamea, but fewer 
than in the canker wood. They are not uncommon in the wood 
of other genera of the Abietineae. * 
In trunks and branches with several canker spots (jig. 2) the 
wood of the apparently healthy portions of the stems between 
the swellings contains chains of pathogenic resin-canals. These 
chains are present in the apparently normal wood, even at a distance 
of 20 cm. from the canker spot (fig. 9). The formation of these 
canals is not due directly to the presence of the fungus mycelium, 
which does not spread more than one to two centimeters outside 
of the canker spot, but to the pathological condition of the whole 
tree when many cankers are formed on its trunk. The chains 
of canals in the canker-wood and those in the apparently normal 
wood at some distance from the canker are similar in every respect. 
The resin-canals in the wood of Adies balsamea affected with 
this fungus are similar in their characters and distribution in the 
rings to the chains of canals found in the normal wood of <Adves 
firma of Japan. According to Dr. Nakamura + the canals in the 
wood of Adies firma are formed only in the fall-wood zone, where 
re el wh in om ASR OE AP HERE TC aah 
they are arranged in a chain or arc, with approximately one canal a 
for every four tracheids. Vertical canals only, and no horizontal 
ones, are formed. The cells lining the canals are also like those 
in Adies balsamea, thick-walled and provided with numerous 
simple pits. 
The resin-canals in A. da/samea are similar also to those formed 
* Mayr, Heinrich, Harz der Nodelpdlzer, Berlin, 80 1894. 
* Nakamura, Dr. Yaroku, Ueber den Anatomischen Bau des Holzes der Wichtig- : 
sten Japanischen Coniferen. Unters. Forst. botan. Inst. Miinchen, 3: 17. 1883. 
