129 
Steil. — Apogamy in Nephrodium hirtipes , Hk. 
8. Thirty-two spores are ordinarily produced in a sporangium of 
Nephrodium hirtipes . The smaller number of spores which sometimes 
occur is to be accounted for by abnormalities in the nuclear condition of the 
spore mother- cell. 
9. A larger number than thirty-two spores is sometimes produced 
by the formation of more than four spores from a single spore mother- 
cell. In rare instances more than eight spore mother-cells appear to be 
produced in a sporangium. Whether in such a case all the spore 
mother-cells can form normal tetrads and spores has not been deter- 
mined. 
To Professor C. E. Allen I wish to express my thanks for helpful 
suggestions and criticisms received during the progress of the foregoing 
investigation. 
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