seg SCRUB ASSOCIATIONS 95 
Examples of Succession I occur on some of the Coal- 
measure plateaux on the eastern Pennines at an altitude of 
about 800 feet (244 m.), of Successions II and III in the cloughs 
of the sandstones and shales (cf. figure 12), and of Succession IV 
in the limestone dales (cf. figure 13). 
The “scrub” of Crump (1904: xxxviii), the “clough thicket” 
of Smith and Moss (1903: 387), the “gill wood” and the 
“hazel copse” of Smith and Rankin (1903: 159 and 173), and 
the “ash copse” of Moss (1907 a: 44) are here included in the 
term scrub which is regarded as the English equivalent of the 
German “ gebiisch.” 
Professor Diels (in Flahault and Schréter, 1910: 19) con- 
siders the use of vernacular names in plant geography very 
questionable. He maintains that such terms are ambiguous 
even in the language to which they belong, that to foreigners 
they are either meaningless or liable to misunderstanding, that 
even if such terms be once strictly defined they will become 
confused again, that they are permanently confusing to people 
unversed in phytogeography, that newly coined expressions 
(e.g., “ Hochmoor” and “high moor”) are not truly indigenous 
terms and are most confusing to non-specialists, and that it is 
therefore desirable to have universal expressions in Latin or 
Greek, and to have these alone. With Diels’ general position 
I have very much sympathy; but it is quite impossible, even 
if it be desirable, to abolish vernacular terms even when these 
do lead to some confusion. Diels specially singles out the 
English term “scrub” as a phytogeographical nomen confusum ; 
and to this might be added the English terms “ forest?,” 
“heath?” and “swamp,” and perhaps indeed every popular 
physiographical and phytogeographical term. It appears to me 
that the only course to adopt is to use vernacular names in 
the most frequently accepted sense, and, in addition, to use 
universal names which are not capable of misunderstanding. 
1 “Forest,” in English, may signify almost any wild, open, uncultivated 
tract of land, not necessarily a tract of woodland, though historical documents 
prove that parts, at least, of the ancient British forests were tree-clad at some 
earlier period. 
Although, in English, a heath is usually a heather-clad tract of land, yet, 
in eastern England, the term is also used to denote a tract of calcareous pasture 
with no heather, as Newmarket Heath and Royston Heath; and in Somerset, 
it is used to designate tracts of deep and often wet peat. 
