FORAMINIFERA. 151 



other Cuttles ; instead of taking their rank, as they 

 are now known to do, among the very simplest develop- 

 ments of animal existence. The chambers communi- 

 cating by several apertures, they were named Fora- 

 minifera ; and that appellation is now found to have 

 a further appropriateness, from the curious fact that 

 their shells, which are formed exclusively of lime, are 

 perforated with minute orifices, often so numerous 

 and approximate as to impart a sieve-like character 

 of the structure. 



About a quarter of a century ago, however, M. 

 Dujardin announced the true condition' of these little 

 creatures. Their soft parts consist of a homogeneous 

 jelly or glaire, without any distinction of organs, which 

 fills the chambers with its clear transparent colourless 

 pulp, and is endowed with the power of pushing out 

 irregular prolongations of its own substance in every 

 direction, and from every part of its surface. These 

 prolongations take the forms of expanded films of 

 excessive tenuity, or lengthened threads, of a viscid 

 semi-fluid, which coalesce and unite by contact, or 

 are separated and drawn out in so great an irregula- 

 rity as to show that they are not enclosed in any skin 

 or membrane. The extensions often reach to a length 

 thrice or four times that of the shell, and may be 

 seen and watched in an interesting manner, when 

 the living Foraminifer is placed in a drop of water 

 within the glasses of an animalcule-cell of the micro- 

 scope, and allowed to remain a few hours -erfectly 

 undisturbed. We see the pseudopodia, as these pro- 



