CONTRIBUTIONS TO THE HISTORY OF THE 
ROTIFERA, OR WHEEL ANIMALCULES .* 
BY PHILIP HENRY GOSSE, F.R.S. 
I. 
THE CROWN ANIMALCULE 
(Steplianoceros Eichhornii ). 
A LITTLE more than a dozen years ago, being then resident 
in London, I became a great frequenter of all the acces- 
sible collections of water in the vicinity of the metropolis. I 
had just purchased a microscope, and, looking with ignorant but 
interested curiosity at some drops of water from a neighbouring 
pool, was charmed with the varied forms and sprightly motions 
of the strange creatures that were disporting there. The result 
was the immediate determination to study and depict these — 
the creatures, namely, that were at that time included under a 
single group, and which had recently been opened up to the 
scientific world by Professor Ehrenberg, of Berlin, in his mag- 
nificent work, Die Infusions-tliieTchen. Since then it has been 
sadly pulled to pieces ; like a block of granite, of which the 
constituent silex and feldspar and mica lie scattered in disinte- 
grated granules, the great class Infusoria, so compact and firm 
as it appeared in the folio of the eminent Prussian microscopist, 
has dissolved under the storms of scientific controversy. One 
runs away with the Rotatoria, another with the Desmiclece, a 
third with the Diatomacece : the Rhizopoda get pickings ; the 
Annelida put in a claim ; and the remainder is so nibbled at, 
that we are fain to huddle away the few sheets of delicate 
engraving that are left in our hands, and hide them in a port- 
folio, for fear that Professor Agassiz should actually fulfil his 
threatening, and swallow up the whole. 
Out of the great mass of strange forms thus brought under 
my notice, I soon selected the Rotatoria, or, as I prefer to call 
them, the Rotifera, as the objects of special attention and 
study ; and for years thenceforth the examination, description, 
* The papers of this series are chiefly intended for students somewhat 
advanced in science ; but, so far as he has been able, the author has aimed 
so to simplify and arrange the matter as to convey intelligible information to 
such readers as have but little previous acquaintance with microscopical 
Natural History and Physiology. 
