368 
Bower.— A Criticism , and a 
tective leaf of the male plant, and to its brown colour ; the 
leaves of the female plant are also destitute of chlorophyll, 
and Haberlandt 1 has stated that c assimilating foliage-leaves 
are entirely absent in the Buxbaumiae,’ while he has further 
drawn attention to the apparent saprophytic habit of the 
rhizoids, their colourless thin membranes, and their frequent, 
mycelium-like anastomoses, as they traverse the humus in 
which they grow. Professor Goebel, in discussing these 
characters, points out truly that there is as yet no proof that 
Buxbaumia is actually saprophytic ; but it would appear that, 
for the purposes of his argument, the burden of proof of this 
point will lie with him. Before conclusions can safely be 
drawn whether or not Buxbaumia is, as he suggests, ‘an 
ancient type of moss which still retains a number of primitive 
characters,’ it will be necessary to be more precisely informed 
on the point of its nutrition : if Buxbaumia really derives part 
of its nourishment as a saprophyte from the humus, there will 
be strong probability that the simplicity of its structure would 
be due to the reduction which usually follows such a habit. 
If, as Goebel suggests 2 , the rotten tree-trunk acts only as 
a sponge, to hold water, and if the moss would grow equally 
well on a porous, inorganic substratum, such an observation 
would remove a serious objection to its being regarded as 
a primitive type : at present we are not informed on this point, 
and must, therefore, withhold a definite opinion. A further 
fact, mentioned and figured by Schimper 3 , and noted also by 
Professor Goebel, appears to me to be very suggestive : he 
describes 4 how, though the young leaves of the female plant 
show no special peculiarities, the peripheral cells of the older 
leaves grow out into filaments with brown walls ; some of 
these do not develop further, others grow into true protonema, 
while others, again, penetrating the soil, and elongating as 
rhizoids, ‘ convey nourishment to the plant.’ The question is, 
What nourishment do they bring to this female plant, which, 
1 Pringsh., Jahrb. XVII, Heft. 3, p. 480, &c. 
3 Bryol. Europ. vol. iv, suppl. 
2 Flora, 1892, p. 101. 
4 Flora, 1892, p. 102. 
