Bulletin de l'Institut Océanographique 



(Fondation ALBERT I", Prince de Monaco) 

 N" 400. — 20 Septembre 192 1. 



A New Classification of Animais. 



Austin H. CLARK. 



In the following pages an attempt is made to group the 

 animal ph3'la according to the progressive economic perfection 

 of the various types, and at the same time to point out the 

 correspondencies and differences between animals and plants. 



While it is not to be expected that any close correspondence 

 will be found between the inorganic and organic worlds it is 

 an interesting fact that, as pointed out by D'' Henry S. 

 Washington, potassium and magnesium on the one hand and 

 sodium and iron on the other tend to vary together in igneous 

 magmas and in the minerals formed from them ; that is, 

 igneous rocks and minerals which are high in potassium contain 

 much magnesium and but little iron, while if the rock or 

 mineral be dominantly sodic iron will be high and magnesium 

 low if these be present. There is an analogous relation of these 

 pairs of elements in the organic world, magnesium and 

 potassium being essential to vegetable metabolism, the other 

 pair being of minor importance, while iron and sodium are 

 necessary for animal metabolism, magnesium and potassium 

 very much less so. 



All organic forms may be interpreted as falling under one 

 or other of the six systems of ciystallization. All animals, 

 Protozoa and the morul^e and blastulas of the higher types, are 

 ultimately reducible to the isometric system, with three equal 

 axes at right angles to each other. Plants, on the other hand, 

 are all fundamentally reducible to the orthorhombic system, 

 with three unequal axes at right angles to each other, or to the 



