128 
LEUCOCIRCA. 
designate as new ; for not being figured, it is totally 
impossible to identify them with the loose and 
vague descriptions drawn up at a time when orni- 
thology comparatively was in its infancy. 
We have not, as yet, been able to determine 
w'hether Rkipidura or Leucocirca should he viewed 
as the pre-eminent type of this genus. If we con- 
sidered that this station should be assigned to that 
division which, from what we yet know, shows the 
greatest developement of the tail, joined to a supe- 
rior length and strength of foot, then Leucocirca 
must have the preference ; but if we regard the 
greatest difference in the form of the bill from that 
so common among the typical flycatchers ( Musci- 
capa ), then we must place Rkipidura at the head 
of this genus. This point, however, is not of great 
moment to our present object, seeing that we have 
only just began to understand • something of the 
whole group, which will probably be enriched, 
in a few years, with double the number of species 
now known. There can be no doubt, however, 
that the two sub-genera now described are the 
typical and sub-typical forms ; a conclusion which 
may be drawn, not merely from their following 
each other in absolute affinity, but from the nature 
of the others, to w r hich we now proceed. 
It will be perceived, by a reference to the table 
already given, that the genus Rkipidura, as a 
whole , is succeeded by that of Muscicapa; it fol- 
lows, therefore, that the type w r hich comes next 
should resemble a Muscicapa more than does 
