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names once given and published were thenceforth unchangeable. 
It is rather unfortunate that the laws which govern the formation 
of languages in general were not more consulted, for it would 
then have been seen that the proper rule to adopt would have 
been unchangeability of names in use, rather than priority of 
date, which latter rule ought only to have*been brought in, to 
decide on the claims of two or more names in use, not to revive 
obsolete names never in use or long ago rejected. Yet even as a 
matter of justice, it may be maintained that we should recognise the 
careful and elaborate definitions of a Doubleday or Westwood, 
rather than the childish guesses of a Hiibner; and should quote 
the former as the authority for the genus, even should they, out 
of courtesy, have adopted the names of the latter. I think too, 
that until they can agree among themselves to a new set of rules, 
English Naturalists should feel themselves bound to follow the 
rules adopted and confirmed by their national scientific Associa- 
tion, and strongly oppose any alterations of nomenclature not 
sanctioned by those rules. We are all agreed that change and 
instability of nomenclature are great evils. We should insist, 
therefore, that whenever one of these rules can be so interpreted 
as to avoid change, it should be done ; and whenever there is any 
doubt as to the interpretation, the benefit of the doubt should be 
given to all names which have been in general use for a number 
of years. If this view is adopted, the proper course to be taken 
is to reinstate every name which of late years has been made to 
give place to one of Hiibner’s, and further, to treat the 
‘Verzeichniss bekannter Schmetterlinge’ as a mere catalogue 
which can never be quoted as an authority for genera. There is 
one other class of alterations made by Mr. Kirby for which I can 
find no rule, and which seems to me to have no advantages 
Whenever the genus from which a family name has been formed 
is abolished for any cause, he at once gives a new name to the 
family. Thus, having abolished Eurygona, Bois., in favour of 
Euselasia, Hiibn., he changes Mr. Bates’ sub-family Eurygonine 
into Euselasiine, and, for the same reason, our old friends the 
Erycinide are rebaptised Lemoniide. It will be remembered 
that for some years the genus Nymphalis was expunged from our 
catalogues, but no inconvenience or confusion was caused during 
that epoch by retaining the old family name of Nymphalide. 
Looking at the varied opinions expressed and acted upon by 
