170 ANIMAL ECOLOGY 



" (b) Lower part with mosses and liverworts (damper 

 than last owing to run-off from the trunk, and 

 height often only a foot, but varying according 

 to the aspect). 



" 3. Hazel undergrowth, with some other shrubs. 



"4. Herbaceous undergrowth. 



"5. Litter of dead leaves, etc. ; or 6. Moss carpet. 



" 7. Soil, underground." 



10. This listing of habitats does not take very long to 

 carry out, and is absolutely essential. Wherever possible the 

 co-operation of a plant ecologist should be enlisted, in order 

 that the plant associations may be accurately determined. 

 But often it is sufficient to make lists of plants yourself 

 from each of the habitat divisions (perhaps with the aid of 

 some field botanist who knows the species well). Druce's 

 Botanisfs Pocket-hook^^ is extremely useful for accurate 

 identification of British plants. When this has been done, the 

 next thing is to start collecting the animals from these different 

 habitats, and in doing this there are several points to be borne 

 in mind. First, it is vitally important to make as full notes as 

 possible on the animals, and to record full details of the exact 

 habitat, e.g. the species of plant on which they are found, 

 whether they were on the upper or on the lower sides of the 

 leaves, and any other observations made at the time, such as 

 the reaction to light or rain, or food-habits, or numbers. The 

 last is especially important. The data can either be written 

 on a label with the specimen or, what is usually more con- 

 venient, a number can be placed in the tube or box containing 

 the specimen and a corresponding number entered against the 

 notes upon it in your notebook. A rather convenient method 

 of making notes is to carry a few record cards such as are used 

 for a card index, instead of the usual notebook. On the other 

 hand, if a notebook is used, it is possible to take a carbon copy 

 at the time, which may often be useful. Usually, however, 

 it is impossible to make anything but very brief and rough 

 notes in the field, and they have to be written up carefully at 

 home afterwards. It is customary to warn students that they 

 must make notes on the spoty and not afterwards. A trained 



