Shaw.— The Fertilization of Onoclea . 263 
as consisting of a chromatic body formed from the nucleus of 
the mother-cell, and an achromatic band formed from the 
cytoplasm of the mother-cell. Strasburger himself described 
in detail the development of the spermatozoid of Osmunda 1 } 
and the mature spermatozoid of Phegopteris Giesbrechtii 2 as 
it appeared when stained with fuchsin-iodine green. He 
found the two anterior coils to stain red, and these he 
considered to be of cytoplasmic origin ; while the posterior 
coil took the blue colour characteristic of the nucleus. The 
cilia he found distributed along the forward coil some distance 
from the end, and the middle coil, he suggested, might have 
contained the centrosome, if there had been one. At present 3 
he is inclined to think that there is no individualized centro- 
some in the spermatozoid of Pteridophytes. He found by 
treating the spermatozoid of Marsilia 4 with the same stain 
and allowing it to fade, that only the hinder and larger of the 
ten or twelve coils contain the nucleus, which extends forward 
to the region where the cilia are attached. In following the 
development of the spermatozoid of Onoclea , Campbell 5 was 
unable to find that so large a part of the forward end is of 
cytoplasmic origin as Strasburger 0 described for Osmunda and 
Phegopteris. ‘ The body of the free spermatozoid,’ the former 
writes, ‘ has the form of a flattened band with thickened 
edges, which tapers to a fine point at the anterior end, but is 
broader and blunter behind V This description fits the living 
spermatozoid as it is to be seen when caught in the slime 
about the open archegonia. 
The principal accounts of the spermatozoid after its entrance 
into the egg are those of Campbell. In studying the develop- 
ment of Pilularia 8 he found the spermatozoid within the egg 
close to the egg-nucleus. It had become a spherical granular 
nucleus darker than the egg-nucleus and with little more than 
1 Strasburger ’92, p. 114. 2 1 . c., p. 116. 
3 Id. ’97, p. 420. 4 Id. ’92, p. 122. 
5 Campbell ’95, p. 312. 6 Strasburger ’92, pp. 115-116. 
7 Campbell ’95, p. 313. 
8 Id. ’88, p. 249 ; ’95, p. 405 ; for fig. cf. also Wilson ’96, p. 106. 
T 2 
