273 
of Eclmhurgh, Session 1883-84. 
a contracted amoeba), as representing tlie amoeboid form. A distinct 
assumption of the amoeboid state at the close of the ciliated one, is 
sometimes to be observed, — as lately by Reinke* in Bangia. And 
thus the cycle is complete, save only for the plasmodial phase. 
The importance of this view for the Protophytes then, is scarcely 
less than for the Protozoa. With a tendency of the encysted state to 
predominance, more marked even than in the Gregarines, the other 
phases are by no means obliterated, and we thus — and only thus — 
obtain an intelligible explanation of that alternation between the 
resting and the motile phase which is so frequent and so charac- 
teristic. The inevitable applicability of this to classification, and 
the light it yields, will be sufficient!}^ obvious. "Without prematurely 
proposing a detailed classification, it will be obvious that we must 
regard those forms, which like Torula, exhibit only the resting state, 
not as primitive, but as exceedingly specialised, and those which 
exhibit more and more of the cycle as less so. 
3. Affinities of the Myxomijcetes . — Passing to the Myxomycetes, 
it will at once be evident, that unless the present theory can, be 
entirely overturned, they have no place among the fungi proper — 
where it is the encysted phase that predominates, the others being 
greatly reduced or suppressed; but are in fact morphologically as 
remote from these as are the monads. The Myxomycetes must be 
placed next Protomyxa ; in fact, Frotomyxa is simply the least 
differentiated known Myxomycete. Their higher forms are interest- 
ing — first, in very frequently showing less of the ciliated stage, and 
secondly (a more important character, since here they are unique 
among living beings), in affording an enormous differentiation of 
their plasmodial stage ; the complicated forms which many of them 
exhibit being simply those of their plasmodial froth, to which per- 
manent shape is then given by the formation of a cellulose envelope. 
The resemblance to fungi is thus as purely superficial and adaptive 
as that, for instance, of Hy droids to Polyzoa, and, like it, is of physio- 
logical interest alone. 
4. The Protista S — The general non-adoption of Hseckel’s pro- 
posal of a third intermediate Regnum Protisticum, has been due to 
three main reasons, — of which the first is that the proposal seems only 
to double the difficulty, since it does not enable us to distinguish 
* Mitthcil. d. Zool. Stat. in Neajjel., 1883. 
