Disease of Greengage Trees. 209 
Many cases were found in which an oblique junction occurred as 
shown by the condition of the cortical tissues (Fig. 2); but upon 
cutting sections through such a branch below the outward line of 
demarcation it was found that the pith and first-formed rings of 
wood were also diseased. In fact a cylinder of diseased wood might 
be present which extended some considerable distance (1-2 feet) 
beyond the region of the infected cortical tissues. Cases with a 
fairly straight although oblique junction were also observed in which 
there was no central cylinder of diseased tissue which penetrated 
beyond the outer limit of discolouration. It was in these cases that 
most gumming was observed at the actual junction of healthy and 
diseased tissue, the latter being much discoloured particularly at 
the line of demarcation. 
Fig. 1. Fig. 2. 
Fig. 1. Dermatella prunastvi Pers. on greengage branches : a, apothecia ; 
the needle-like projections are pycnidia. Nat. size. 
Fig. 2. Dermatella prunastvi Pers. on greengage branches: a, upper, and b, 
lower limit of an oblique junction area ; the bark has been stripped off showing 
the discoloured wood above and to the right of the line a b. Two-thirds 
nat. size. 
Upon examining more minutely a dead branch which bore 
fructifications, the button shaped apothecia were seen scattered 
sparsely among the very numerous pycnidia. Both fructifications 
were black in colour. Some clusters of pycnidia and apothecia 
arose together; both, however, occurred separately in twos and 
threes or singly. 
