Recent Literature. 
1883.] 
105 
In a few instances Mr. Sharpe admits subspecies, as under Troglodytes 
domestica , where fiarkmani, aztecus , and insularis are thus treated, but 
such cases are exceptional ; the local races of Tkryothorus ludovicianus 
and T. beivicki are each accorded full specific rank, although spoken of as 
‘‘forms” of the species to which they are referred as races by American 
writers. His criterion for subspecies is therefore, to say the least, obscure. 
Ha rft o rhyn ckus rufus longirostris is not only raised to the rank of a 
species, but is separated from rufus. by two intervening species, and is not 
even spoken of as having a near relationship to H. rufus . Finally on this 
point it may be sufficient to state that in the “subfamilies” T roglodytince 
and Mi mince no subspecies are admitted outside of the genus Troglodytes, 
with the single exception of a West Indian form of Mimus. As in former 
volumes, there is, as a rule, no direct comparison between closely allied 
species further than that very inadequately furnished by the “ key” to the 
species standing at the head of each genus. We note a few changes of 
names, among them Camfylorhynckus couesi for what has commonly been 
called C. brunneicapillus , the latter name belonging properly to C. a finis 
auct., for which it is here substituted. 
In respect to the classification followed in these volumes, Mr. Sharpe 
states that it is based on that of the late Professor Sundevall. While he 
adopts his higher divisions (“cohorts”) of the Passeres, the arrangement 
of the lesser groups bears little resemblance to the confessedly artificial 
arrangement devised by Sundevall. While in the main Mr. Sharpe brings 
the minor groups into more natural relationship, his relegation of the 
Dippers (family Cinclidce auct.) to the position of a genus in the subfam- 
ily of Wrens is, to say the least, novel if not unwarranted, while the 
Ptilorhynchince and some other groups find themselves among decidedly 
new associates. 
The preface to volume VI (dated December, 1881) states: “It is hoped 
that the succeeding volume (which will conclude the Timeliidce, and which 
has made considerable progress) will appear within the space of a twelve- 
month, as also that, with additional extraneous help, the work generally 
will make more rapid progress than has hitherto been possible.” That 
such will be the case is earnestly to be hoped, so great is the value of the 
work to all general students of ornithology. — J. A. A. 
Birds and Insects.* — Our best authority upon the insect food of birds 
has continued his observations upon the subject. Professor Forbes set 
himself to answer the three following questions: 1. Do birds originate 
any oscillations among the species of insects upon which they feed? 2. Do 
they prevent or restrain any oscillations of insects now noxious, or capa- 
ble of becoming so if permitted to increase^ more freely ? 3. Do they do 
anything to reduce existing oscillations of injurious insects? 4. Do they 
sometimes vary their food habits so far as to neglect their more usual food 
*The Regulative Action of Birds upon Insect Oscillations. By S. A. Forbes. Bull. 
No. 6, Illinois State Laboratory of Nat. Hist., Dec. 1882, pp. 1-3 1. 
