DRY-ROT OF INCENSE CEDAE. 11 



dition invariably showed that they had been developed successively, 

 or at least not more than two in the same year. But on dead down 

 trees the above rule does not hold. Of the seven known occurrences 

 (see p. 9) several trees had two or more fresh sporophores. 



During the course of the actual work of dissecting the trees exact 

 data were secured on three sporophores and 17 shot-hole cups dis- 

 tributed on 15 trees, as follows: Two abortive sporophores on separate 

 trees, one normal sporophore and two shot-hole cups on the same 

 tree, 10 shot-hole cups on separate trees, 2 shot-hole cups on the 

 same tree, and 3 shot-hole cups on the same tree. 



That there might be a definite orientation of the sporophores in 

 standing living trees was suggested by the work with Trametes pini of 

 Moller (18), in which he found 89.4 per cent of the sporophores on the 

 westerly side of the trees, attributing this to the facts that the pre- 

 vailing winds were from the west, the trees were most strongly struck 

 by rain on the west side, and therefore the branch stubs (a very com- 

 mon point of infection) were more moist on that side. Furthermore, 

 he states that the sporophores appear at the same spot at which the 

 infection commences. Weir and Hubert (32, p. 30), working with 

 the Indian-paint fungus (EcMnodontium tinctorium) on western hem- 

 lock (Tsuga Tieterophylla) , found that most of the sporophores had a 

 northwest to north-northeast orientation. However, the sporo- 

 phores and shot-hole cups of Polyporus amarus are rather equally 

 distributed to all points of the compass, showing no definite relation 

 to any particular direction, and in not a single case was the sporophore 

 developed at the same point at which the infection apparently com- 

 menced. 



These sporophores and shot-hole cups occurred on trees ranging 

 from 24.2 to 44.2 inches diameter breast high. The youngest tree 

 which bore a shot-hole cup was 193 years old at stump height (1.5 

 feet), the next youngest was 221 years of age (28 years older), and 

 the oldest, 379 years. Between the ages of 193 and 379 years the 

 trees with sporophores or shot-hole cups were rather equally dis- 

 tributed. These figures are not given for the purpose of establishing 

 a diameter breast high or age range for trees in which Polyporus 

 amarus fruits; the number of trees examined forms entirely too 

 meager a basis. 



Sporophore formation did not seem to be in any way related to the 

 width of the sapwood, since the sapwood in the trees which had 

 formed sporophores varied from comparatively narrow in some cases 

 to rather wide in others. 



The heights at which the sporophores and shot-hole cups were 

 found varied from 9.6 feet to 48.7 feet from the ground level, but 

 thirteen of them occurred between 15 and 30 feet and only two at a 

 greater height than the latter figure. Sporophores or shot-hole cups 



