Variation in the use of certain scientific terms and 
changes in the spelling of scientific names, 
DEIN Y, HOEyMANS NEN EAS AS A 
In a short paper entitled « Type and Typical », which I contri- 
buted to « The Canadian Entomologist » and which was published 
in volume XL, page 141, I wrote : 
« These terms are used in such different senses by different 
authors, that confusion is sometimes caused, and it is much to be 
desired that some authoritative body of naturalists should accura- 
tely define their proper use, and then that all other naturalists 
should accept the decision and conform to it, even if it does not 
agree with their own individual opinions. » 
Mr. CHARLES OWEN WATERHOUSE proposed selecting one 
specimen only as type and calling all other specimens that the 
author had before him, when describing a species, co-types, and 
has many followers. 
Mr. OLDFIELD THOMAS and others use the word co-types for 
all the specimens before an author when no single type is selected, 
saying « the type in such cases equalling the sum of the co-types ». 
Mr. THOMAS added : « No species would have both type and co- 
types, but. either the former or two or more of the latter ». 
Mr. THOMAS proposed the word para-types to be used for the 
specimens which Mr. WATERHOUSE called co-types. Others 
again use the word type or types for all the specimens an author 
retains in his own collection or specially deposits in some national 
museum, and call those distributed to other museums or private 
collection co-types. 
