— 
Retrospective Criticism. 87 
ness to those exquisite specimens, the joint production of 
these two artists, which adorn some of the early Numbers of 
your Magazine, and are so justly and universally admired. 
I have no wish, however, to find fault with subordinate parts, 
where there is so much reason to be satisfied with the 
whole. The substitution of the wooden vignette in the 
room of the aquatinta engraving is an exchange greatly for 
the better, like that effected of old,.xpiczx yaaxziav — gold 
in lieu of brass. There is also one additional plate in the 
same style as those in the first edition, representing a new 
or little known species of agaric, and likewise four or five 
other wood-engravings. Among the latter, that which shows 
the singular diversity of forms in the small scales (commonly 
called meal or dust) which cover the wings of lepidopterous 
insects, opens to us a wide field of interesting enquiry. How 
infinite is the variety which Nature displays even in her 
smallest works, and where, to the eye of a common observer, 
the objects seem uniform and alike! And how much closer 
an inspection will they bear, than the fairest works of art! 
And here I would just throw out a hint for the use of the 
practical entomologist, and suggest, whether the examination 
of these minute parts under a high power of the microscope, 
might not possibly, in some intricate cases, be of service to- 
wards distinguishing species from mere varieties. Where but 
slight discriminating marks appear obvious between two in- 
sects, if it should turn out, on microscopic inspection, that the 
scales of the two taken from corresponding portions of the 
wings, are of dissimilar forms in each, the stoutest advocate 
for the non-multiplication of species could hardly resist such 
evidence of the two insects being really distinct. 
Besides the additional plates, there is, in the second edition, 
a considerable portion of fresh matter in the letter-press. Of 
the value of such new matter, the reader may judge by the 
following interesting extract, which is the only one I will 
make, having already extended my remarks to a much greater 
length than I at first anticipated. 
‘* Rural sounds,” observes the author, ‘‘ the voices, the lan- 
guage of the wild creatures, as heard by the naturalist, belong 
to, and are in concord with, the country only. Our sight, 
our smell, may, perhaps, be deceived for an interval by con- 
servatories, horticultural arts, and bowers of sweets; but our 
hearing can in no way be beguiled by any semblance of what 
is heard in the grove or the field. ‘The hum, the murmur, 
the medley of the mead, is peculiarly its own, admits of no 
imitation; and the voices of our birds convey particular intima- 
tion, and distinctly notify the various periods of the year, with 
G 4 
