390 SEA-SIDE STUDIES. 



respect to Hydra viridis, in which repeated examinations 

 have disclosed nothing of the kind ; in Hydra fusca I have 

 seen it often, but the observation by no means warrants 

 the conclusion that this proof of the network being cellu- 

 lar is a proof of its being muscular. The cells resemble 

 muscles in no respect, except that they are contractile ; 

 and we are not warranted in calling every contractile cell a 

 muscle-cell ; otherwise we must call the unicellular aiiimals 

 muscles* The Hydra presents us with contractile substance 

 (or cells), but to call the contractile substance a " muscle," 

 is to outrage language more than if a wheelbarrow were 

 spoken of as a raihvay locomotive ; and even this latitude 

 of language will not serve our turn with respect to the 

 nervous system of the Polype, smce nothing resemblmg a 

 nerve or nerve-substance is discernible in it. We must eithei- 

 deny that the Polyjse manifests Sensibility, or we must admit 

 that Sensibility may exist without nerves. 



In presence of these facts, physiologists, who cannot con- 

 ceive Sensibility without a nervous system, but are forced to 

 confess that such a system is undiscoverable, assume that it 

 exists " in a diffused state." I have noticed tliis illogical 

 position in a former Chapter. It is a flat contradiction in 

 terms : a diffused nerve is tantamount to a liquid ciystal ; the 

 nerve being as specific in its structure, and in the properties 

 belonging to that structure, as a crystal is. Now, this spe- 

 cific stmcture — or anything approaching it — is not to be 

 found in the Polype.-|- 



• Victor Carus and Reichert have discovered contractile cells in the vitel- 

 lus, but no one would call these muscles, 

 t " Sarcbbe una vera perdita di tempo," says Delle Chiaje, "per colui 



