hein) 
Some take a very wide view of what is a type. One entomo- 
logist, in giving a list of the types in his collection, says that 
he considers as a type any specimen sent to him by the 
describer of a species. Others regard all the specimens which 
they had before them when describing a new species as types, 
and distribute them as such. Some thirty-five years ago I 
saw the danger arising from this loose way of using the word, 
and applied the word “type” to the actual specimen de- 
seribed when that could be determined, and called the other 
examples mentioned by an author ‘co-types.” Some years 
afterwards my colleague Mr. Oldfield Thomas proposed 
(P.Z.8., 1898, p. 242) the terms para-type, topo-type and 
meta-type ; and all these are useful in their way. But we 
are both agreed that the word type should be restricted to the 
actual specimen upon which the species is founded. 
I think describers should make their descriptions from a 
specimen which is to be the standard specimen for all future 
reference, and should mark it as such. Other specimens 
associated with it may have the same value, but very often 
they have not. A case lately came under my notice where a 
series of specimens, all named by the describer as one species, 
were found when examined carefully by a specialist to con- 
sist of five distinct species. In this case there was no special 
difficulty in saying for which species the name should be 
retained, but sometimes it is very difficult. When an author 
has confused two species and his description is applicable to 
both, any one who subsequently discovers the error is at 
liberty to say to which of the two the name should be applied, 
and may describe the second as a new species, the division 
of the species following the same course as the division of a 
genus where no type has been specially indicated. The type 
specimen therefore, according to the view I take, is the 
STANDARD SpecIMEN for all future reference ; it should be as 
carefully preserved as are our standards of weights and 
measures, for we must frequently refer to them if we are to 
have accurately named specimens. 
I know from experience that it is quite possible to compare 
a specimen with a type and to be satisfied that your specimen 
belongs to the same species, and afterwards to find that there 
