42 MICROSCOPICAL OBJECTS FOUND 



of which we perceived the digestive apparatus of 

 the Polype."* 



This is a totally different result from what 

 ensues on submitting a recent Rosalina or Trun- 

 catulina to the same test. In the latter case, 

 what is left, instead of preserving the contour of 

 the exterior, is in reality a cast of the interior of 

 the calcareous portion, apparently the identical 

 lining membrane, the absence of which from the 

 cells of Eschara attracted the notice of Milne 

 Edwards. Hence it is probable that the cell of 

 the Foraminifer is more analogous to the poly 

 pedom of the Hydroida, which. Dr. Johnston 

 remarks, is " a sheath, disconnected, or at least 

 not in organic union, with the soft pulpous matter 

 which it invests and protects." 



It must be some prolongation of this skin, or 

 membrane, that constitutes the pseudopodia. 

 The latter cannot proceed from the calcareous 

 case, but from the animal contained in it, 

 which pushes them forward through the fora- 

 mina in the former. At the same time they 

 can scarcely have proceeded as distinct organs, 



* History of the British Zoophytes, by George Johnston, 

 M.D. p. 327. 



