HYDRA. 181 



escape notice, unless its previous situation were 

 accurately observed. 



It might be asked by what power is this 

 animal, occupying so low a place in the scale 

 of organization, enabled to perform these ac- 

 tions? To this question, however, no satisfac- 

 tory answer has yet been given. The substance 

 of the hydra, when examined by the microscope, 

 appears to be nearly homogeneous, except that a 

 number of grains are intermixed with the pulpy 

 and gelatinous matter composing the principal 

 bulk of the body. These grains, when pressed 

 out of the flesh into water, are scattered indis- 

 criminately ; and appear to have been united 

 in the living animal, by means of this glutinous 

 material. 



No perceptible fibres, either muscular, or of 

 any other kind, can be detected in the flesh of 

 the polypus : nor is there the least indication 

 of the formation of transverse rings, similar to 

 those which exist in worms, and which, in these 

 latter animals, contribute to progressive motion. 

 Every portion of the substance of the body is 

 equally irritable and contractile, and its move- 

 ments appear to be governed by some voluntary 

 power belonging to the animal, and directed to 

 the attainment of certain ends. The softness 

 and pliancy which it possesses allow of its being 

 closely fitted to all the inequalities of the sur- 

 face of the bodies to which it is applied ; and 

 perhaps this cause alone occasions it to adhere 



