2 
BRITISH BEETLES. 
are useful to the ordinary student for all practical 
purposes, but cannot be retained, in the present state 
of our knowledge, as scientifically accurate, as the 
Tunicata (containing the Ascidians), and the curious 
little Lancelet ( Amphioxus ) form more or less strong 
connecting links, and cannot be definitely classed with 
either division. 
For a full account of the classification of the 
Animal Kingdom which is now generally followed, the 
student is referred to the Elementary Text Book ot 
Zoology by Dr. C. Claus (translated by Sedgwick and 
Heathcote in 1884) and to the second edition of 
Professor Rolleston’s “ Forms of Animal Life,” by Mr. 
W. Hackett Jackson (1888) : in a work like the present 
it is, of course, only possible to give a very short 
account indeed of the- chief divisions, which may either 
be regarded as seven in number, viz. — the Protozoa, 
Coelenterata, Vermes, Echinodermata, Arthropoda, 
Mollusc a and Chordata (the last of these including the 
whole of the Yertebrata and the Tunicata and Am- 
phioxus before referred to), or perhaps more correctly 
as ten, the list standing as above with the omission of 
the Chordata and the addition of the Molluscoidea, 
Tunicata (or Urochorda), Cephalo chorda, and Vertebrata. 
The Protozoa are the lowest forms of life ; in the 
simplest cases they are composed of a nearly or 
altogether structureless jelly-like substance, with no 
definite body cavity, and no marked alimentary 
apparatus : the best-known members of this section 
are the Amoeba, or Proteus-animalcule, which is a mere 
microscopic lump of jelly which moves along by 
thrusting out and withdrawing portions of its body 
substance ; the Foraminifera, which have the power of 
