48 
MAS8EE ON MUCORS. 
“ Judging from the case of fungi, there is no reason why the side 
issues of flowering plants, characterized by absence of chlorophyll, 
should not become so thoroughly differentiated from the parent 
stock as to constitute a distinct group, phanerogamic fungi. 
“ In like manner, it is not necessary to assume only one point of 
departure for the fungi from the alga*, but the close agreement 
between the Saprolegniece and certain algae indicates the origin of 
the fungi, and shows also that between the two examples given the 
point of divergence is not wide. It is observable in almost every 
instance of a marked departure from a typical group, that the 
earliest departures remain stereotyped at a certain stage of develop- 
ment as a group, characterized by features partly their own and 
partly those of their arcestors ; connecting links, in fact. Certain 
elastic members of this first group in turn develop new features, 
and where the new departure is able to hold its ground in the struggle 
for existence, this process of evolving new morphological and 
physiological factors, a process generally contemporaneous with the 
obliteration of the original characteristics of the stock from which 
the new type originated, is repeated, until eventually a group of 
organisms is produced possessing strongly marked features in 
common, and only in touch with the group from which it evolved in 
the possession of those characters common to all plants. 
“ In illustration of the above, it may be mentioned that in those 
sections of fungi, of which the mushroom and puff-ball are character- 
istic, there is not the remotest indication, morphologically or physio- 
logically, not even in the earliest phase of development, of any 
affinity with the algas, and it is only by means of tracing the 
origin of these terminal groups of fungi from others lower in the 
scale of fungal differentiation that their true origin and sequence 
can be determined. From what has been said respecting the 
evolution of the fungi from the algae, and also of the sequence 
from the most highly differentiated to the primitive group of fungi, 
there is the danger on the part of the reader of assuming that the 
origin and sequence of development of the fungi is fairly complete. 
To guard against any misconception it is important to state clearly 
that such is not the case ; it is generally admitted that the fungi 
are of algal origin, and, further, that the main divisions of fungi are 
connected with each to such an extent that the idea of independent 
starting points is not suggested ; but it must be remembered that 
each of the main sections in which fungi are naturally divided is 
composed of several smaller sections, and the sequence of origin and 
affinity between these minor sections are yet far from being settled. 
We may conclude this portion of the subject by stating that the 
most fascinating branch of biology — embodied in the term (life- 
history) — can alone indicate the required evidence for a satisfactory 
solution of the affinities between the various sections.” 
The volume is neatly printed, and there is an index of terms, 
an index of plant and animal hosts, and a systematic index at the 
end.— M.C.C. 
