250 
eurylaimin.®:. 
llhipidura and Platystomus. In this manner we 
might test these two circles through the whole class 
of ornithology, and gain the same results ; for as 
every natural group is hut a representation, under 
different modifications, of the five primary types of 
Nature, it follows, that if they agree with one, they 
will agree with all. In regard to the aberrant sub- 
families, represented by the genus Querula, Psaris, 
and Fluvicola, the circles, though imperfect, are 
proved to be natural, for they hare their represen- 
tations in the two we have been comparing ; and, 
therefore, if they belong to this family at all, — and 
this cannot admit of a doubt, — they will follow 
each other in the order we have placed them : and 
this point, also, has been established by the preced- 
ing analysis. Before the discovery of Platystomus, 
the affinity of Qtieru 7 a to the Eurylaimina might 
have been doubtful ; but it seems to he no longer so. 
And, setting aside all other considerations, these 
two birds alone agree in the curved form of the 
commissure ; while the Paehyrhynchus pectoralis 
connects Querula, on the other side, to the great 
series of the Muscicapidm, through Psariance and 
Fluvicolince. Future discoveries will no doubt fill 
up the smaller links, and probably alter some of the 
location of the types ; but, until that period arrives, 
we know not any fact or argument sufficiently strong 
to induce us to suspect the general principles of the 
arrangement of the family to which this volume of 
the Naturalist’s Library has been devoted. 
