32 THE CANADIAN ENTOMOLOGIST 
shewing the head in profile, and the neuration of both wings. Ten 
excellent plates in colour are given portraying 350 species. 
The collaboration of three specialists of such recognized 
standing as Lord Walsingham, Mr. J H. Durrant, his assistant, 
and of Mr. August Busck, has resulted in a valuable production 
which commands careful and respectful consideration. 
The conclusion that secondary sexual characters should be 
discarded, as a means for delimiting genera, while not a new one, 
as stated by the author, has not won the universal approval that 
should be accorded it. Lord Walsingham is, therefore, to be con- 
gratulated on having been the first to apply this principle in such a 
comprehensive manner, A list of genera in which these characters 
are eliminated as a means of generic classification has, of course, 
led to the sinking of a number of old and well established names as 
synonyms. Under Eucosma Hb., for example, are placed such 
familiar names as Epihlema Hb., Epinotia Hb., and Thiodia Hb. 
The bibliographical work has been done most thoroughly 
and will make this work indispensable to all who specialize within 
the groups treated. 
Attention is called, by the author, to the necessity for more 
careful work in the description of neuration, and to the fact that 
it is necessary, in most cases, to denude the wing and study it 
under the miscroscope. This is undoubtedly true and too much 
reliance should not be placed upon descriptions based upon older 
and more inadequate methods. The writer wishes to call particular 
attention to the helpfulness of the many drawings illustrating the 
text, and regrets that it was not possible to carry out this plan of 
illustration for every genus described as new. An adequate verbal 
description of the neuration of a new genus, for example, is doubt- 
less possible, but doubtless also it is seldom, if ever, given. 
The writer is informed that, by an unusually thoughtful 
arrangement, drawings of unique types were placed, where speci- 
mens of the insects were lacking, with either the British or the 
United States Museum. This feature has added greatly to the 
usefulness of the book itself and of the collections of the two 
museums mentioned. 
