1916] MEINECKE: PERIDERMIUM AND CRONARTIUM 233 



material into the wounds. Two of the wounds were left open, not ban- 

 daged. The others were wrapped in cotton and paper or protected by 

 paper bags. The bandage was left on for a number of days. The wrap- 

 ping made it necessary to cut off the bundles of needles in the neighbor- 

 hood of the wounds. No. II was treated on May 23, 1913 in a number 

 of places without wounding. The places chosen for inoculation were 

 sprayed before and after the application of the spores. Here also the 

 needles were cut. In other places dry spore material was dusted on 

 after cutting the impeding needles and spraying. A sporulating gall 

 was tied to a twig. All inoculations were protected by paper bags. All 

 inoculated places were marked with colored twine. 



Ill and IV were not inoculated. Ill was allowed to stand in a room 

 together with I and II. IV was kept in a separate room. 



A prolonged absence made regular inspections impossible. The plants, 

 however, were sprayed regularly. 



In December of 1913 several distinct oblong swellings, suggestive of 

 Peridermium harknessii galls, were discovered on tree No. I on places 

 inoculated in May. No. II also seemed to show a swelling in one place. 

 This plant, however, soon began to decline and finally died. Immediately 

 above the swellings on the younger parts of the living plant adventive 

 buds began to sprout in the characteristic manner of witches'- broom 

 formation so commonly observed above the galls of Peridermium harknessii. 

 The other two plants of Pinus radiata remained in perfect health as did 

 all other parts of the inoculated plant. Even No. Ill, which had been 

 standing close to the infected plants for more than seven months showed 

 no sign of infection. > 



During the winter of 1913-1914 the swellings, which had now become 

 so typical that in nature one would without hesitation classify them as 

 young galls of Peridermium harknessii, remained more or less stationary. 

 No signs of pycnia or of aecia were apparent. The risk of losing the plants 

 in the unfavorable conditions of a city laboratory made it advisable to 

 transfer the trees to the open. On March 12, 1914 the remaining plants, 

 Nos. I, III and IV were planted close together in the experimental gar- 

 den of the Campus of the University of California, Berkeley, California. 

 All through the year of 1914 the swellings were more or less stationary; 

 the witches'-brooms became, if anything, a little more distinct. No signs 

 of pycnia or aecia appeared. An inspection on March 3, 1915 brought 

 the final result. The swellings on No. I had increased somewhat in size; 

 the witches'-broom formation was very plain. Aecia had broken out, in 

 each case in the very point of inoculation, indicated by a slight depression. 



The photograph (figure 1) shows plainly the gall, with the aecium, 

 and the beginning witches'-broom formation above. 



