CUCULIFORMES. 
rank also, but not include it in the same family. The third is also divided 
into two, Pyrrhocentor, Centropus, Coica (?) and Geococcyx, Crotophaga and 
Guira. This arrangement is certainly in need of emendation and Centropus 
is commonly regarded as standing alone in the Order. 
The extra-limital birds classed as Cuckoos show such varied forms that 
many genera are necessarily accepted even by the genus-lumper. It is 
probable that many families will later be used when the anatomy of the 
forms is thoroughly investigated. As above noted, three or four families 
should be used in conjunction with Australian representatives, viz., Cuculidce, 
Eudynamisidce, Scythropidce and Centropodidee, the doubtful one being the 
second named. Superficially it might be classed in the Cuculidce, but it has 
many resemblances in its osteology to Scythrops, but it should not be classed 
with that very distinct group on account of these, as just as many differences 
can be recorded. 
The distinctness of the Centropodidce will later be shown, but here it may 
be observed that they habitually make their own nests and rear their young, 
a feature very uncommon in the Order, and that they constitute a compact 
group ranging from Africa, through southern Asia to Austraha, almost 
unchanged as to coloration as well as structure, indicating that they are quite 
an ancient group. 
The superficial characters of members of the Order are the zygodactyle 
feet, peculiar bill, and tail of ten feathers (two extra-limital genera have eight 
only). As suggested above, the Order seems somewhat of a heterogeneous nature 
and it is probable that later detailed anatomical study will enable the differentia- 
tion of the perplexing elements. Thus the Centropodidce need careful criticism 
from every point of view, so that their exact relationships can be exposed. 
Again, an interesting item is the evolution of Scythrops, as it is quite an aberrant 
form at present. Eudynamys also needs consideration, especially with relation 
to Urodynamis, while the isolation of this last-named group is an extraordinary 
feature. All appear to be migrants to a greater or less extent, but the movements 
of the Austrahan species are more or less local, so that they can almost be 
considered non-migratory, as the latter term is commonly used. The distribution 
over the earth’s surface is also worthy of attention in consideration with their 
evolution, as many species are now restricted to small areas. 
As characteristic, may be noted their parasitical habits, and so much has 
been written concerning these that a full volume could easily be prepared 
covering extracts, discussions, etc., of the habits, reasons and theories. In 
this place I propose scarcely to touch upon the points in dispute, but would 
merely note that the “ Cuckoo ” lays one or more eggs, apparently upon the 
ground, and thence transfers the egg by means of its biU to the nest of a small 
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