INTKODUCTORY 3 



one animal is quite beyond his powers, and he would 

 find this out as he went on. He would begin, per- 

 haps, by stating the locality in which he found the 

 specimen, the only locality in which it was at the time 

 known to occur. This statement is the Geographical 

 Distribution or Zoogeography of the animal, and is one 

 aspect of animal description. It is, in other words, 

 its distribution in Space as far as is known. He 

 would then probably proceed to describe the general 

 form and appearance of the animal — its shape, colour, 

 possession of limbs, wings, fins, and other obvious 

 external structures, or the absence of these. If 

 minute in size, he would examine it under the 

 microscope ; if large, he would examine its internal 

 structure by dissection. This is a second aspect of 

 the animal, that of ' its structure or Morphology. This 

 includes both naked-eye and microscopic structures. 

 By this study he would determine on what plan the 

 animal is built up, and as the result of the knowledge 

 thus gained he would be able to say whether the 

 animal was a bird, fish, insect, and so on. This is the 

 aspect of animals which is most studied in zoological 

 laboratories, but which the field naturalist usually 

 does not spend much time over. He is much more 

 interested in recording and observing how the animal 

 lives its life, and adapts itself to its surroundings. 

 The functions performed by all the structures of the 

 body interest him more than the method on which 

 those structures are built up. In describing his dis- 



