582 DR. J. B. HICKS ON THE GONIDIA AND 
of the cells. Every terminal cell seemed ready to separate, or had already done so. Each 
was divided by a septum into two portions ; after separation, the cells began to increase, 
and the contents became darker, more homogeneous, and ultimately they possessed the 
appearance of a Chlorococcus, and underwent subdivision. 
Retrospect. — In reviewing the points of interest contained in the foregoing communica- 
tion, I shall take them in the order in which they have been presented. And the first 
which seems to stand most pro min ent is, 
1. The peculiar tendency of the confervoid filaments to grow for any indefinite period 
and extent in the same form and state, both in and out of water ; so that it is not to be 
wondered at that they should have been considered independent vegetations. This 
opinion appears still more excusable when it is considered that they can reproduce them- 
selves by any one of their cells, which sometimes, becoming free and globular, presents the 
appearance of a spore. How much more would it have been justified had the knowledge 
of their segmentation, &c, been then possessed ? It gives another instance of the im- 
portance of the study of the entire life-history of all forms. We are much indebted to 
Kiitzing (whose studies have had generally an opposite tendency) for first pointing out 
the true nature and origin of these so-called Algae. 
At the same time, may I not ask, does it not make us question the origin of many of 
the Confervoids, the tracing of whose whole history we have never achieved, of whose 
sexual life we have no knowledge ? Of how many do we know only the vegetative 
growth, with its formation of active (zoospores) gonidia and passive gonidia ! Let us 
not conclude these to be finally placed, but let us follow them through by every possible 
way, in order to detect all their phases of existence. 
The remark of Braun applies to this subject, as well as to those which follow : — " The 
greatest care is requisite in their determination as independent organisms ; nor should 
this be decided unless every stage of their evolution, from beginning to end, is known" *. 
I can only add, When are we to know when we have found both or either ? 
2. The second thought which seems worthy of detention arises from the circumstance 
that, out of these confervoid filaments, two or three genera with numerous species of Algae 
have been founded. J?rotonema, Gongrosira, and certainly some forms ofChroolepus are not 
Algge, but the varying forms of these Moss-productions. "We might well feel our faith 
in specific and even generic distinctions in general staggered by these and similar facts, 
but more particularly in respect to the Confervoidese. We are bound to suspend our im- 
plicit trust in the certainty of their position, at least as to many whose history is as yet 
undetermined. It might be brought forward as an apology, that these forms were really 
distinct, each kind belonging to separate Mosses. In answer, I might say that a few 
observations would readily show that this excuse could not be sustained; for I have 
reason to believe that nearly all the varieties can be produced from each one of the 
Mosses, if placed under varying conditions. 
The different forms of the confervoid filament, as I have already shown, depend on 
external circumstances, rather than on the species to which they belong, although it 
is possible that some exceptions may be found to this rule. The value of the distinctive 
* Braun, on Unicellular Algee, Mic. Journ., vol. v. p. 91. 
