75 
Fig. 60. Longitudinal section through the pre-anal gland (ef. fig. 31). 
ce. the cells composing the gland. 
tt. the internal cavities with ciliated epithelium. 
s. the yellow secretion with black pigment. 
N. nerve-branch to the gland, coming from the posterior pedal 
ganglion. 
CORRIGENDA. 
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