ENDOTHIA PARASITICA AND RELATED SPECIES. 61 



Inoculations with Endothia gyrosa were also made on numerous 

 hosts from which it had never been reported. Six or more inocu- 

 lations were made on each host, in the manner described above, ex- 

 cept that a part of each series was left unwrapped. The following 

 inoculations showed no growth whatever: Those made in Virginia, 

 April 4, 1914, on Cornus florida, Fraxinus americana, Juglans cinerea, 

 Ilex opaca, Sassafras variifolium; in Maryland, April 17 and 22, 

 1914, on Carya glabra, Cornus florida, Liriodendron tulipifera, Nyssa 

 sylvatica, /Sassafras variifolium, and Quercus alba; and in New 

 York, July 11, 1914, on Betula alba, Prunus serotina, Populus trem- 

 uloides, Rhus glabra, Salix sp., and Sassafras variifolium. On Acer 

 pennsylvanicum and Carya two out of the six inoculations developed 

 a few stromata. These were found only on the tissue injured by 

 the cut and there was no evidence of parasitism. 



On Castanea, Fagus, Quercus, and Liquidambar, however, a branch 

 inoculated as described above dies back rather faster than the checks. 

 This would indicate, as suggested by Clinton (18, p. 419), that 

 E. gyrosa is a weak parasite ; that is, that it is able to invade injured 

 and dying tissue. 



It is evident from Table III that Endothia gyrosa coming from 

 any of the four hosts named will, under favorable circumstances, 

 grow on any of the others. Several other interesting facts are 

 brought out by the table. Inoculations made with material from 

 Liquidambar grew in general more rapidly on Liquidambar than 

 on any of the other hosts. In many cases, material from Liquidam- 

 bar failed to grow on Castanea, Fagus, and Quercus, and even when 

 inoculations were successful growth was somewhat slower and pyc- 

 nidial production less abundant. 



On the other hand, inoculations from Fagus, Quercus, and 

 Castanea usually grew less rapidly on Liquidambar than on any 

 of the other three hosts. This is, of course, what would be expected 

 from the systematic relationships of the host species, and while the 

 inoculations made are too few to permit any definite conclusions 

 they are nevertheless suggestive. As shown by Table III, Quercus 

 prinus proved a very unfavorable host for Endothia gyrosa. 



In all cases inoculations made in the fall (Sept. 15) failed 

 to show any growth until the following spring. This corresponds 

 with the results in inoculations of Endothia parasitica, but it is, of 

 course, impossible to determine whether this failure to grow is due 

 to the dormant condition of the host or to unfavorable weather con- 

 ditions. Perhaps correlated with the results just noted are the 

 unusually poor results obtained from inoculations made in the early 

 spring. It will be noted that inoculations made on April 2, 1914, 

 were in general much less successful than those made on May 23, 

 1914, in exactly the same locality and in many cases on the same 

 hosts. 



