Fig. 2. cases, to produce a new slime-mold in all respects comparable to its polymorphic ancestry, a new motile organism ready once more to break up into spores and fruit, and so continue its never-ending cycle of purposeless existence. I say purposeless, for there seems to be no outlet, no outlook toward anything better or higher. Its relations look backward, not forward, and we connect it with the lowest forms of animal life more easily than with anything else. Hence the difficulty of the systematist. Animals they can hardly be, for nowhere else in the kingdom are animals reproduced by spores, to say nothing of the forms of fruiting described later on. We call them for convenience fungi; yet, while some fungi are destitute of mycelium, and some produce swarm spores or motile naked amœboid spores, still in no instance do these behave as in the slime-mold.
It is interesting to notice the gingerly manner in which naturalists in their discussions approach these forms. Sachs throws in a chapter, nowhere in particular, a sort of addendum on Myxomycetes. De Bary, the lamented, gives us his masterpiece on fungi, "including the Mycetozoa," and in speaking of their relationship says, "For various reasons, which, according to the knowledge at hand, have from time to time been more or less closely worked out, I have, since 1858, placed the Myxomycetes (slime-molds) under the name Mycetozoa outside the vegetable kingdom, and this I still consider their proper place." He does not call the organisms animals, be it observed. If a zoölogist chooses to do so, De Bary makes no objection. Meanwhile, Saville Kent, zoölogist, encouraged probably by De Bary's position, comes forward in
- De Bary, "Morphology and Biology of Fungi," p. 478.