of the Genera of the Aranee. 53 
all, then the disputation is at least confined to the inter- 
pretation of the strict letter of the law of priority. 
The original spelling, therefore, of each name is given in 
every case in this revision; for although it is true that 
Micromata may oftend the classical eye, just as the asso- 
ciations also gathered round certain names are swept away 
and feelings wounded by any alteration in the nomenclature, 
still something must be sacrificed for the sake of uniformity, 
and it is better to sacrifice feelings, which are transient, than 
to tamper with printed facts, which will, at any rate, outlive 
authors, sentiments, and associations. 
The object held in view, then, is to ascertain what is the type 
species of every group which has ever received a name, and 
briefly to give the reasons why such a species must be 
regarded as the type. 
No attempt is here made to determine whether this or that 
generic group ought to be maintained or not, but simply to 
settle what, if a genus is maintained, must be the type 
Species representing that genus, exclusive of any other 
species. 
This attitude naturally involves the following of some 
definite system, which shall be consistently applied throughout 
and no deviation from it admitted on any consideration 
whatever. 
The Principles of Elimination. 
The system followed in the determination of types where 
no type has been definitely selected is known as that of 
“ Elimination,’ by which the last species left in, of those 
originally included in the genus when first published, becomes 
the type, supposing the group to be broken up into other 
genera by the author himself or by subsequent authors. 
If, however, the author himself or another author has 
definitely selected a type for the genus, either from all those 
originally included or from the two or more species left in, 
the species thus selected is regarded as the type, whether it 
be the oldest species or not. On no account can a species 
not originally included in the group become the type of the 
genus, even though added subsequently by the author him- 
self or definitely selected by that author as the type. 
Species are often eliminated by “ ¢mplication” in other 
genera. For instance, supposing three species were originally 
referred to a certain generic name and an author subsequently 
founds a genus upon another species not originally included 
but afterwards found to be congenertc with one of the ori- 
ginal: this original species is then regarded as removed from 
