98 TlMEHRL 
to be of the simplest stru&ure imaginable, destitute of 
any kind of organisation, presenting the aspe6l simply of 
minute specks of a jelly-like substance comparable to the 
albumen or unboiled white of an egg, a substance known 
as " sarcode" or " protoplasm/' the {i physical basis of 
life ;" yet, on the other hand, many, in comparison with 
these, possess a high degree of organisation, which, 
however, in comparison with that of the higher animals 
such as the beasts, birds, reptiles or fishes, or even the 
inse6ls or worms, can only be considered as of a very 
rudimentary kind. 
The basis or ground substance of life, this protoplasm, 
is in every case the same, and is most easily perceived at 
the beginning of the life of the minute animal, when its 
chara6ler has not yet been interfered with by growth — a 
condition that is as absolutely characteristic of all other 
animals, whether highly organised or not. 
The absence or simplicity of organisation in the 
Animalcules is noteworthy. In the higher forms of 
animal life, we are familiar with a complicated apparatus, 
or body, made up of an internal supporting tissue, or 
skeleton ; of a sensory or nervous tissue for sensation, 
with its brain, column and branching nerves ; of a muscu- 
lar system for motion, in intimate relation with the 
skeleton and nerve tissue ; of a circulatory or blood 
system, with its central heart, and its ramification of 
vessels, large and small, carrying nutriment to every 
portion of the body ; of a respiratory or breathing system, 
aerating the blood or nutrient fluid, and, aided by 
secretory and excretory organs, keeping it pure and 
wholesome ; of a digestive system, providing for the 
manufacture of this blood or nutrient fluid; and of a 
