1 903 British Field Zoology 69 



British Field Zoology. 



By various Writers. 



Chapter I. — Introductory. 



The series of articles under this heading, which are to begin in our 

 next issue, are intended to bring the subject of Animal Life before field 

 naturalists in a comprehensive way. That is, the various Classes, 

 Orders, and Species which together make up the British Fauna will be 

 treated from the field-work point of view mainly, whilst at the same 

 time their other aspects will be sufficiently dealt with to complete the 

 picture. The simplest forms of life will be studied first, — the one-celled 

 animals — then the more complex. Minute details will be avoided as 

 such, but will be studied where they are necessary to understand general 

 principles. 



The very first thing that the field naturalist should know about the 

 animal kingdom is what the description of an animal involves. That 

 is by no means such a simple matter as might appear. It may be 

 explained by an illustration. Suppose for a moment that the observer 

 discovers an animal which, as far as he is able to ascertain, is some- 

 thing which has not been described before, a new species. He is 

 anxious to draw up a description of it to present to a meeting of some 

 society, so that his hearers may get a complete idea of his discovery. 

 He will probably find that the task of fully describing one animal is 

 quite beyond his powers, and he would find this out as he went on. He 

 would begin perhaps by stating the locality in which he found the 

 specimen, the only locality in which it was at present 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 ani- 

 mal, 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 sur- 

 roundings. The functions performed by all the structures of the body 



