lis Transactions. — Miscellaneom. 



find this matter. Professor Huxley has aptly designated it, " The physical 

 hasis of life." lu fact, it may be termed " life -stuff," to use a form of 

 expression lately come into vogue. This " life-stuff " has received the name 

 of protoplasm from the Greek Trpwrog and xXao-^a, meaning the first 

 formation. 



The simplest form in which this protoplasm has as yet been found, may 

 sometimes be discovered if a drop of an infusion of some animal or vege- 

 table substance which has been allowed to stand a few days, be placed 

 under the microscope. There, if the magnifying power be sufficient, you 

 may see a minute mass of jelly-like substance, looking very like a particle 

 of white of egg escaped from its shell. Watch it, however, and you will 

 quickly perceive that although it is to all appea]'ance structureless, it is 

 never for a single instant at rest. It is continually changing its shape — 

 pushing out first at one side and then at another finger-like projections, 

 which extend a certain distance and are then retracted, to be followed only 

 by further extensions and retractions in other directions. Occasionally two 

 of these little streams of semi-fluid stuff will meet and unite into one, or 

 the end of it will apparently fix itself to the glass, and the main body will 

 draw itself up to it, thus producing a tardy kind of locomotion. These 

 jelly-like bodies are not always perfectly clear, often their substance is occu- 

 pied by minute dots, or by a spot which has the appearance of an empty 

 space, and which is in consequence termed a vacuole. If you find one of 

 the dotted bodies, you will see the dots running through the interior of the 

 body, racing up the protrusions as they are formed and again returning when 

 they are withdrawn, showing thus that the matter within the cell is in a 

 state of continual motion. If you are fortunate enough to see a minute 

 animal or vegetable come within the grasp of the finger-like protrusions 

 when this jelly-like being is hungry you will see that it is gradually di-awn 

 towards the central portion, which slowly changes its elastic shape so as to 

 form a hollow in which the particle of food is enclosed, and in which it is 

 digested. The digested portion becomes absorbed, and the bit of jelly, if 

 there be any indigestible part left, quietly opens out either at the place 

 where the food was admitted or some other place, and exudes it. This 

 organism has received the name of Amoeba, or Proteus Animalcula, from 

 the perpetual variations takmg place in its shape, and it is probably the 

 simplest form in which we are able to recognize those phenomena of irrita- 

 bility and mobihty which we desigcate life. 



In the vegetable kingdom we find bodies of a very similar kind, minute, 

 simple, single cells, either apparently empty or containing green or red 

 colouring matter ; and which sometimes are stationary, at others whirl and 

 gyrate round the field of view in a manner which contrasts strongly with 



