1871.3 Al 
the very essence of the studies of the naturalist ought to be the exposure and ob- 
literation of error; there can, in an exact science, be no ‘“‘common error.” It is 
true that the names of insects, or of any other natural productions, are not science 
in themselves, but they form an integral portion of science, and a common error 
can no more become law with them than in any other branch,—biology, for instance. 
I agree with Mr. Lewis that ‘‘it is expedient to have no more synonymy,’— 
the word is the naturalists’ béte noire ; but the idea that it can be summarily put a 
stop to is profoundly Utopian. It is expedient there should be no more crime, no 
more deceit, in the world; and, as a consequence, no more prisons, police, and 
lawyers. But the evils exist, and the other necessary evils are required to keep 
them in check. Synonymy exists, and its existence renders necessary the evil that 
entomologists must waste precious time in unravelling it. The suppression of 
both crime and synonymy by a jiat is utterly impossible. I couple the words, but 
the existence of synonymy is too often owing to what are actual crimes against 
science. I hold that, when an entomologist describes an insect as new, without 
using every endeavour that is humanly possible to discover whether it be not already 
described, he commits one of the greatest of crimes against science. Mr. Lewis would 
condone this; and, byapplying his maxim “communis error facit jus,” absolve the evil- 
doers, and make their crime a virtue. Here again, it seems to me, that he shows the 
predispositions of the amateur, or, of the visionary. When that millennium shall arrive 
when everything is understood thoroughly all over the world, and the truth be com- 
pletely arrived at in the natural way (not partially by a glorification of error), thereneed 
be no more synonymy : synonymic lists will then be “ functi officiis:” till then it 
is to be hoped that we shall have many of them (there cannot be too many if con- 
scientiously compiled), with all the synonyms, even if they extend to a page in 
length, fully enumerated under each species. 
It is hardly necessary to explain that the foregoing remarks are made from a 
general point of view, and not from a lcpidopterological one only. Having com- 
menced my entomological studies as a lepidopterist, though possibly only as an 
amateur, it needs no great amount of discernment to make obvious to me the fact 
that British Macro-lepidopterists stand urgently in need of a thoroughly scien- 
tific monograph. Mr. Lewis’s criticisms in his paper in our last number, and at the 
Entomological Society, show that he should possess the acquirements necessary for 
its production. Let us hope our lepidopterists are tired of the degrading publica- 
tions that have been recently submitted to them; works in which descriptions and 
advertisements are unblushingly and inextricably blended. If, then, he will prepare 
such a work (and include synonymy), he will obtain the gratitude of his fellow- 
labourers ; or, at any rate, by being able to arrange his collections after his own 
method, he will be spared the annoyance originating from the change effected by, 
and the want of unanimity in, the works of others.—R. McLacuian, Lewisham, 
12th June, 1871. 
On the rules and use of Synonymy: in reply to Mr. W. A. Lewis.—Mr. Lewis does 
not appear to have quite understood the passage which he has quoted in the cur- 
rent volume of Ent. M. Mag., p.3., from one of my letters ; and a full explanation is 
therefore desirable. Inmy paper on the Generic Nomenclature of Diurnal Lepidop- 
tera (Journ. Linn. Soc., vol x, pp. 494—503), I observed that, “we must either 
