NATURAL HISTORY SOCIETY OF GLASGOW. 119 



elevation of 2000 feet, or about 800 feet above the high level of 

 the Field lands; (3) Beech tracts, or lower mountain slopes, say to 

 an elevation of about 3000 feet; (4) Pine tracts, or central 

 mountain slopes, 4000 to 5000 feet; and (5) Lichen tracts, or 

 upper mountain slopes and summits, 5000 feet to about 8000 

 feet. 



So much, then, for the division of an area into districts. 



As regards migratory movements, I think, as far as possible, all 

 records connected with this subject should be kept separate from 

 those of distribution. I am aware that it is not possible altogether 

 to ignore migration in a treatment of distribution, but we can, to 

 a certain extent, give such records a secondary importance, by 

 recording simply the occurrence of such species and no more, 

 leaving for a separate table of migratory movements the entry of 

 more detail. 



We now come to the use of symbols as a means of expressing 

 the faunal value of the species in the columns. 



Professor Newton of Cambridge, in a Paper in the " Transac- 

 tions of the Norfolk and Norwich Natural History Society," 

 (1870-1, p. 24), has explained a method of registering Natural 

 History observations, which his brother and himself followed out 

 during a period of ten years' residence at Elv^den, in Norfolk. 

 By those who are desirous of keeping exact daily records of 

 migratory movements, I believe no better plan can be followed, 

 and I would recommend to such a careful study of his article. 

 Professor Newton tells us : — " However good an out-door naturalist 

 any man may be, let him adopt the plan here described, and he 

 will become a better one " (p. 29), as the keeping of such records 

 " ensured continuously our careful attention, forcing us to take 

 notice of everything that caught the eye." I will only further say 

 here that Professor Newton recommends what I may call a 

 inogressive system of symbols, having its chief recommendation 

 in its " variability, combined with simplicity," and " a capability 

 of expressing various meanings, especially in combination, 

 and its freedom from complication." Bearing this advice in 

 view, I would then suggest for approval the following code of 

 symbols for recording observations on Distribution, and which 

 can be used either in the field for daily work, or in the 

 study for bringing into workable order the records of previous 

 authors. 



