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I e lesions examined many larvae have shown marked 
degeneration with a well-developed necrosis of the surrounding 
tissues, while other forms have n well preserved, and have 
caused little or no necrosis of the tissues. This suggests that, 
ently been dead, but the retrogressive processes vary markedly 
In extent in different tumours. 
In the older lesions it is not possible to determine the 
exact nature of the material contained in the circular or 
ovoid spaces in the necrotic areas, but in the light of the 
knowledge gained from examining earlier lesions, there can 
be no doubt that the material is the débris of a larval 
Nematode. 
It must be insisted here that in the older lesions one may 
be unable to detect any degenerated larvae, or even the 
spaces which they at one time occupied. This fact renders it 
important that the histopathological picture in all its vari- 
ations should be thoroughly studied and understood. If this 
diagnosis can usually be made, in spite of the fact 
that no casual organism can be demonstra 
The foregoing descriptions of the microscopic appearances 
apply equally to tumours from the penis and from the sheath, 
except that in the latter situation the tissue reaction is far 
oh marked and the necrotic areas more diffusely scattered 
roughout the tumour. In both situations there may be 
marked endothelial proliferation in the intima of the 
oe. This is often seen in the deeper parts of the 
mour. Sometimes there is thrombosis of the vessels. The 
uecrotic areas, however, are in no way associated with the 
These areas are 
nfiltration of all the tissues with 
. There is little formation of new tissue apart from 
