236 The Naturalst in La Plata. 
species known. And yet with the exception of 
that dry husk of knowledge, concerning size, form 
and colouration, which classifiers and cataloguers ob- 
tain from specimens, very little indeed—scarcely any- 
thing, in fact—is known about the Tree-creepers; and 
it would not be too much to say that there are many 
comparatively obscure and uninteresting species in 
Europe, any one of which has a larger literature 
than the entire Tree-creeper family. No separate 
work about these birds has seen the hght, even in 
these days of monographs; but the reason of this 
comparative neglect is not far to seek. In the 
absence of any knowledge, except of the most frag- 
mentary kind, of the life-habits of exotic species, the 
monoeraph-makers of the Old World naturally take 
up only the mostimportant groups—1.e. the groups 
which most readily attract the traveller’s eye with 
their gay conspicuous colouring, and which have 
acquired a wide celebrity. We thus have a suc- 
cession of splendid and expensive works dealing 
separately with such groups as woodpeckers, trogons, 
humming-birds, tanagers, king-fishers, and birds of 
paradise; for with these, even if there be nothing 
to record beyond the usual dreary details and 
technicalities concerning geographical distribution, 
variations in size and markings of different species, 
&ec., the little interest of the letter-press is com- 
pensated for in the accompanying plates, which are 
now produced on a scale of magnitude, and with so 
ereat a degree of perfection, as regards brillant 
colouring, spirited attitudes and general fidelity to 
nature, that leaves little further improvement in this 
direction to be looked for. ‘The Tree-creeper's, being 
