570 
H. V. WILSON 
clear from this quotation that Parker has seen the same elongated 
epitheUoid cells which I have described as lining the large efferent 
canals. My precise observations were limited to these canals, 
but I may say that I doubt if both an epithelium and an outer 
sphincter-like layer of myocytes bound any of the canals. 
Round the osculum the case must be different. Parker here 
finds a well marked sphincter. 
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