443 
Mnium affine , var. ciliaris ( Grev .), C.M. 
crescent shape, becomes homogeneous in appearance, and closely applied to 
the blepharoplast. The latter extends forward as a narrow thread termi¬ 
nating in a thickened head which bears two cilia. 
The writer has spent some time in studying certain of these features in 
Porella, Marchantia , Fegatella , and Blasia. A statement made in regard 
to the development of the sperm of Blasia (8) seems to be quite as appli¬ 
cable to the three others just mentioned. It seems also to be true of Riccia 
Frostii as described by Black. ‘ The blepharoplast makes its appearance 
first as a dense area of cytoplasm in opposite ends, respectively, of each of 
the pair of spermatids. Gradually a definite granule or body is differentiated, 
which develops as a thread or cord around the cell near to the plasma 
membrane. This cord, the blepharoplast, stains homogeneously through¬ 
out. Following its course the nucleus lengthens in close contact with the 
blepharoplast, the two become indistinguishable by the time one complete 
turn is made, and the body of the sperm, which stains like chromatin, con¬ 
tinues to increase in length until the mature form is reached. Two cilia are 
developed probably from the forward end.’ The writer has not observed 
in these forms the ‘ cytoplasmatischer Fortsatz the ‘ limosphere ’, or the 
‘ chromatoiden Nebenkorper’ referred to above. While polar bodies were 
observed occupying the respective poles of the last division in Marchantia , 
it was not found possible to trace them as bodies of morphological rank 
throughout the telophase of this division. 
When we compare these results obtained from the Liverworts with 
those recently described for species of Moss by Wilson, Allen, and Walker, 
there seems to be a considerable difference in respect to the details of 
development. Recent investigation, however, has led me to believe that 
the difference is not so great as at first seems apparent. It might be well 
at this point to call attention, on the other hand, to certain phenomena which 
seem to be quite constant, judging from recent reports, throughout spermato¬ 
genesis in both groups of the Bryophyta. Obviously there is a general 
agreement as to the form of the mature sperm. This body consists of 
a crescent-shaped, curved, or coiled slender portion representing nuclear 
material, while projecting beyond one extremity, which may be termed the 
anterior end, is the blepharoplast bearing two very delicate slender cilia. 
Occasionally a vesicle is attached to the posterior portion of the sperm. 
The exact character of this vesicle remains as yet somewhat uncertain. 
Walker ( 5 ) considers the vesicle to be made up largely of extruded chro¬ 
matin, Wilson (6) thinks that material extruded from the nucleus is present 
in the vesicle, while Black (2) and Woodburn (7 and 8) have referred to it 
as cytoplasmic in nature. 
Practically all of the writers too agree quite closely in their descriptions 
and figures of the early stages of the androcyte. This cell consists of 
a well-defined and relatively large nucleus, a surrounding zone of cytoplasm 
Gg 3 
