Note 18 — THE NORTH AMERICAN SLIME-MOULDS

In discussing these species the reader may be referred to Professor Harper's study of cytology, Bot. Gazette, vol. XXX., p. 217. It is probable that in all these æthalioid forms the effect of disturbance, transfer to laboratory, is likely to be quite pronounced. Giant spores are often seen, doubtless due to arrested cleavage in the procedure described by Dr. Harper: a giant spore is penultimate or antepenultimate in series; should, on this theory, occasionally, at least, show more than one nucleus.