Simple Forms of Life. 199 



speaking, a cell is a chamber of some sort enclosed on all 

 sides, and physiologists employed it to designate a little 

 chamber, or space, enclosed by a membrane or tissue, and 

 holding inside it living matter. It is not necessary that we 

 should explain the details of cellular physiology as it was laid 

 down a few years since, as scientific men have pretty well 

 agreed that it must be greatly modified, and it is impossible 

 to avoid recognizing the fact that the functions of life may be 

 performed by little globules or molecules of appropriate mat- 

 ter, which are not surrounded by any distinct membrane or 

 wall. It is, however, probable that the smallest living object 

 consists of matter in at least two states, and if from no other 

 cause than the influence of position, the outside layer will 

 differ more or less from the inner portions.* It might appear 

 difficult to conceive of a simpler animal than an amoeba, but a 

 high power shows that the gelatinous material, or sarcode, of 

 which it is composed contains a number of spherical mole- 

 cules or granules, and any one of them, if isolated and capable 

 of sustaining its life, might, perhaps, represent what, if we 

 adopt the cellular nomenclature, might be called a unicellular 

 creature. 



The amoeba, in its simplest state, is an illustration of life, 

 with predatory habits and considerable activity, carried on 

 without the help of positive organs. Former numbers of the 

 Intellectual Observer have described the villous projection, 

 discovered by Dr. Wallich, in certain forms of this creature, 

 and it also possesses an apparatus for reproduction, as he has 

 shown. We may, however, regard all its ordinary proceed- 

 ings as carried on without the aid of distinct organs, although 

 the various globules it contains, and which present no dis- 

 tinctive character to the eye, may still have separate functions 

 to perform. Young microscopists are pretty sure to pass over 

 small delicate amoebae without notice, and it is a mere chance 

 whether they happen to turn upon large easily-noticeable 

 forms. If they have any more experienced friends to help 

 them, they should see an object of this kind as early as they 

 can, as some conception of its appearance and ways is very de- 

 sirable at the commencement of a study of organic beings. 

 We see a mass of jelly moving by the faculty of thrusting out 

 portions of its substance into projections termed pseudopodia, 

 or false feet. Out goes, or rather flows, a dribble of the jelly, 

 extending into prolongations longer and thinner, or thicker 

 and broader, according to the particular specimen under 

 notice. The outside layer (which may soon become the 



* See a former article, Vol. vi. p. 75. The last sentence, page 79, is especiallj 

 applicable. 



