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POrULAR SCIENCE REVIEW, 
the supposed ganglia into two parts, communicating only by a narrow per- 
foration in the diaphragm. The so-called ganglia are, in fact, simply appear- 
ances produced by the j uxtaposition on the two surfaces of a thin diaphragm 
of two masses of granular matter produced by the spreading out, on these 
surfaces, of the central cord of the corresponding joint. 
The supposed nerve which runs from the basal ganglion of the zooecium 
to the bud is actually attached, as Fritz Muller thought, to the intestine of 
the adult polypide, but, according to M. Joliet, it is nothing but the organ 
described by previous authors under the name of the fimicle. It has the 
same structure as the central cord, and it is so contractile as to act the 
part of a third retractor muscle. It has therefore no resemblance to a nerve. 
From all these circumstances M. Joliet concludes that this system of 
organs is not nervous in its nature. Further, he finds by experiment that 
pinching or even cutting the central cord has no influence upon the poly- 
pides which might be expected to be acted upon, and hence concludes that 
it does not transmit sensation. He is still engaged in investigating its 
nature, but in the meantime states that the fusiform cells of which it is 
composed may often be seen to swell and become rounded, and then detach 
themselves from their neighbours, giving origin to a number of floating 
corpuscles which are observed in the liquid filling the joints of the stem and 
the cavities of the zocecia of the JBozverbankia. As these Polyzoaare found 
on the British coasts, some of our readers may find an interest during the 
coming vacation time in investigating this curious problem. 
