146 
difference from their recent homologues,” and are in many cases con- 
fined to the immediate vicinity of the same areas occupied by their 
descendants. As there is reason to believe that these beds were 
formed previous to the dissolution of the intermediate land, an incal- 
culable time must have passed without appreciable change. The 
whole of Mr. Wollaston’s introductory remarks are highly suggestive, 
and the work itself bears on every page the evidence of the most 
scrupulous care and research. I am very glad to see that Germat’s 
names, Baris, Sibynia, Magdalis, Hypera, Sitona, &c., so arbitrarily 
changed by Schéuherr, and whose changes have been so blindly 
adopted by other Entomologists, have been restored by Mr. Wol- 
laston.* 
Here I should like to make a few remarks on genera and species, as 
it is a subject which is likely before long to force itself on our atten- 
tion more than it has yet done. I think the conviction is gaining 
ground with all those who are studying species in large numbers, 
that, except in isolated, or what in the present state of our know- 
ledge appear isolated cases, species have no definite limitation. We 
have come to that opinion very generally in regard to genera, but 
in both equal difficulty seems to me to exist, the only difference being 
that we are apt to fix on the idea of an individual to represent the 
species, while we are, to a certain extent, distracted by the species 
which represent the genus; and hence many have come to regard the 
genus as an artificial creation. But although genera cannot be said 
to have an absolute existence any more than species, and can only be 
regarded as expressive of an idea, yet as such they have a relative 
existence. That it is impossible to limit or define them with the 
individual precision necessary to constitute an absolute fact is no 
proof that they are artificial; indeed, when we consider how many 
examples might be brought forward—the majority, perhaps, of large 
* Mr. Wollaston has altered the name of his genus Eremotes, because of its being 
too near Eretmotes: this should, by the same rule, be altered because of Eretmotus. 
Then is not Syntomocerus, which is proposed to replace the former, much too near 
Syntaphocerus ? What is to become of the author’s other genera? Will not Zargus 
be too near Sargus? or Piotes to Piodes? or Melansis to Melasis? or Somatium to 
Stromatium ? or Xenoscelis to Stenoscelis? and so on. Whilst on the subject of 
generic names, may I be permitted to point out that the use of the letter & instead of 
c, for the Greek y, is contrary to the Latin rule, and a very objectionable innovation ? 
I am glad to see that certain German and French authors have restored the purity of 
some names thus disfigured, e.g., Acis for Akis, Acimerus for Akimerus, CEceticus 
for Oiketicus, &c. 
ee 
