work. A list of i Hypothetical Genera ' is ac- 

 companied by pertinent comment ; ' Changes 

 in Form of Names ' covers a consideration of 

 the much-vexed question of the proper treat- 

 ment of ' emended' names. On this point 

 the author says : " Probably no section of the 

 A. O. U. Code has been the subject of so much 

 criticism as Canon XL., which provides that 

 ' the original orthography of a name is to be 

 rigidly preserved, unless a typographical error 

 is evident.' Stability and priority are two 

 of the cardinal principles of the code, but 

 priority is merely a means of securing sta- 

 bility, and applies as well to the adoption of 

 the earliest name as to the earliest form of 

 that name. Experience has shown that any 

 other course leaves the door wide open to 

 emendation and resultant confusion." A 

 number of generic names are cited, having 

 from five to eight variants that have been more 

 or less in use, in illustration of the results of 

 emendation; and in further elucidation of the 

 extent to which emendation may be carried, 

 it is shown that the name Aplodontia, with 

 eight actual variants, ' is capable of at least 

 twenty-four modifications, each one differing 

 from the rest by a single letter.' Some 

 eminent zoologists maintain that a difference 

 of a single letter in two names is sufficient to 

 distinguish them, and to prevent the later 

 name or names (for there are often several) 

 from being thrown out as preoccupied, whether 

 the difference in form is due to gender, to a 

 difference in the connecting vowel in com- 

 pound words, or to the presence or absence of 

 aspirates; while others consider names the 

 same when having the same etymological 

 origin, though differing in form. 



Under ' Rejection of Names ' the author 

 considers at length the following topics : ' Pre- 

 occupied names,' under which is given a most 

 useful ' List of Homonyms within the Class 

 Mammalia; and another list of preoccupied 

 names in mammalogy and ornithology; 'nom- 



