414 Mr. Strickland's Commentary 



So also the group of the Kestrels was first defined as a genus 

 by Boie under the name of Cerchneis ; and this term ought, 

 I conceive, to be retained rather than Tinnunculus, which is 

 merely the name by which Brisson designated the common 

 species of Northern Europe. I shall point out other cases of 

 the same kind below. 



Before proceeding to details, I wish to make a few further 

 suggestions of improvements which might be introduced with 

 advantage in future editions of this work. 



1. In the present work the student is unable to judge what 

 extent Mr. Gray assigns to each genus, no definitions being 

 given, and only one species quoted as an example. In his 

 preface, however, Mr. Gray holds out a prospect of publishing 

 the characters to his genera, a plan which I trust he will 

 execute. At any rate he ought to lose no time in publishing 

 the definitions of all the new genera contained in this work, 

 it being held by some naturalists that to give a generic name 

 without a definition does not constitute an act of publication ; 

 and he is thus exposed to the same kind of petty larceny by 

 which Vieillot anticipated so many of Cuvier's genera. For 

 the same reason Mr. Gray ought to give names at once to all 

 those generic groups which are indicated in the present work 

 without being named. 



2. In all cases where the species quoted as the type of a 

 genus remains unfigured, a reference should be made to some 

 work in which it is described, otherwise the student has no 

 clue to the characters of the genus. 



3. A distinction should be made between those genera 

 which are retained exactly as at first defined by their authors, 

 and those which have undergone subsequent restriction. Ge- 

 nera of the former class may remain with merely the name of 

 the author attached, as Irena, Horsf. Genera which are now 

 confined within more restricted bounds than when originally 

 defined, may be distinguished by the syllable (restr.) after the 

 author's name; thus Corvus, L. (restr.), Sphenura, Licht. 

 (restr.), &c. 



4. In reciting the synonyms to each genus it would be a 

 great improvement to distinguish those terms which are ex- 

 actly equal in extent to the adopted genus, from those which 

 are either more or less comprehensive. The neatest way of 

 expressing this seems to be by means of the algebraic signs 

 > greater than, = equal to, and < less than. Thus I would 

 write Crypsirhina, Vieill., 1816, (restr.), = Temia, Cuv., 

 1817 > = Phrenothrix, Horsf., 1821, < Corvus, Lath., < Coitus, 

 Lath., < Glaucopis,Tem. Again, Conurus, Kuhl, 1820, = 

 Aratinga, Spix, 1824, > Psittacara, Vig., < Psittacus, Shaw, 



