affile; diseases. 189 



Sph(sropsis did not spread more rapidly than Coryneuni and did 

 not do greater damage to the young trees. In each case, some 

 of the inoculations resulted in girdling the branch and killing 

 the part above it, and, in some other cases with each, the spread 

 of the fungus was checked by the development of callus. Some 

 inoculations were also made with Coniothyrium pirina (Sacc.) 

 Sheldon. This fungus did not invade the healthy tissue but 

 grew to some extent in bark which was injured by the inocu- 

 lations. In this my results agree with those of Hartley (3) 

 who carried on extensive inoculation experiments with this 

 fungus. Phyllosticta limitata Pk., Cylindrosporium pomi 

 Brooks, and Bpicoccum granulutum Penz. gave negative results, 

 the wounds healing over almost as readily as the checks. 



Glomorella fructigena (Clinton) Sacc. was also used in mak- 

 ing inoculations on 7 of the one-year-old trees in the green- 

 house. Edgarton (2) has pointed out that there are two forms 

 of this fungus, northern and southern, and that they differ in 

 cultural characters. Inoculations made with material from 

 cultures which agree with the southern form in the develop- 

 ment of perithecia, both in culture and on the inoculated trees, 

 show that this form is much more actively parasitic on the 

 young trees than Coryneum foliicolum or Sphcuropsis malorum. 

 The cultures of this form were obtained from an apple from 

 a grocery in Orono. The northern form which was isolated 

 from both apples and cankers collected out of doors in Orono, 

 grows slowly in culture, has not produced perithecia either in 

 culture or in the cankers and does not spread so rapidly nor do 

 so much damage to the young trees upon inoculation. Nothing 

 has been done in comparing the two forms with Coryneum by 

 inoculation of older trees in the orchard but it is expected that 

 this can be done next year. 



In order to determine the extent to which Coryneum folii- 

 colum is capable of causing disease of branches of apple trees 

 in the orchard, inoculations were made May 21, 1909, in 

 branches one to 3 cm. in diameter on bearing trees. The inoc- 

 ulations were made in the same manner that has been described 

 for the young trees, the inoculated places and check incisions 

 being wrapped in moist absorbent cotton. On the day follow- 

 ing the inoculations the cotton was wet and two days later rains 

 and cloudy weather began which lasted two days. Examina- 



