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mals, the colourless blood-cells, many ncrve-cclls, and very 
many other cells of animals in general, &c. 
2. Lepocyta (or Cclluhe membranosa;) , covered cells. 
Encysted plasma-masses with nucleus, enclosed in an entire 
or incomplete membrane or shell ; for example, the Diato- 
maceac, most young plant-cells (as long as they still possess a 
nucleus), the eggs of most animals, and many animal 
cells in general, &c. 
Manifestly the great interest of the Monera especially 
consists in their being Gymnocytodes, i. e. Plastides of the 
simplest of all kinds, and in the fact that all the above-men- 
tioned kinds of Plastides, as they form the bodies of all 
organisms, are based upon them. Phylogeny, the palaeonto- 
logical development-history of the organic stems (Phyla), is 
necessarily at last compelled to go back to the archigonic 
(originating by spontaneous generation) Monera for the first 
groundwork of all the various groups of organisms. Prom 
the Gymnocytodes, as the original plastide-forms (the very 
simplest, perfectly homogeneous, masses of plasma) , originate, 
on the one side, by outer differentiation of plasma and 
membrane, the Lepocytodes, on the other side, by inner 
differentiation of plasma and nucleus, the cells ; and these 
last then again divide into covered and naked cells, according 
as they are surrounded by a membrane or not. To these 
four primary forms of Plastides all other cells and cell-forms, 
and, generally speaking, all histological elements, can be 
reduced, as I have more fully developed in my General 
Tectology (‘ Gen. Morph.,’ vol. i, pp. 269 — 303). 
Let us now fix, by this scale, the morphological importance 
of all hitherto discovered forms of Monera, as I have classed 
them synoptically in the last section of this memoir, and we 
shall arrive at the following results : 
1. All Monera remain for their lives cytodes ; they never 
develop into the higher condition of the cell, since nuclei arc 
never differentiated in their protoplasm. 
2. All Monera are, in their full-grown and freely moving 
condition, Gymnocytodes ; in this condition they never 
possess a membrane, or shell, or other envelope. 
3. The Gymnomonera (Protogenes, Protamceba, and per- 
haps, also, Myxcdictyum ?) remain throughout their lives 
Gymnocytodes ; they do not pass into a resting condition, 
and they do not surround themselves with a covering. 
4. The Lepomonera (Protomonas, Protomyxa, Vampy- 
rclla, Myxastrum), from being originally Gymnocytodes, 
become afterwards Lepocytodes, during which they pass into 
