82 ON THE CLASSIFICATION OF BIRDS. 
exceed the dimension of that species so common in 
England — the M uscicapa grisolu. The bill, although 
it is rarely so broad as in the last group, is much more 
flattened ; and the bristles at the gape are more de- 
veloped. Their whole structure, also, is more slight — 
and delicate; but their colouring, although sometimes — 
elegant, is almost devoid of vivid tints. The different 
form and length of the bill and feet furnish the charac- — 
ters by which the genera and subgenera are distinguished ; _ 
while the species, which are exceedingly numerous, with 
the exception of the genus T’odus, are only found in 
the Old World. The typical genera are Todus and — 
Muscicapa; the aberrant are Megalophus, Monacha, and — 
-Rhipidura : the two first are so numerous in species as — 
_ to contain subgenera ; and they will, therefore, require 
a more detailed notice than we can give to the others. 
(94.) The recent re-discovery of the genus Mega S 
lophus, — which, although known to Buffon, remained 
lost to modern ornithologists until very lately, — toges 
ther with that of Shrsioahne. nearly at the same time 
has established that immediate reunion between the last 
and the present subfamilies which at once demonstrates 
their close affinity. This genus, at present, is repre- 
sented only by a single bird, the Todus regius of the 
old authors, which seems to inhabit a very limited 
district in Tropical America. It is, in many respects, a 
most extraordinary type, — possessing, like Prion 
among the Laniade, a complete rasorial crest, with the 
short and imperfect feet of the fissirostral structure. 
With such a combination of characters, it is almost diffi- 
cult to say to which type it truly belongs: but such 
instances are by no means uncommon; and, as Rhipi- 
dura, at the opposite side of the circle, has the longest’ 
feet and the largest tail, we may consider the latter ny | 
the rasorial, and Megalophus as the fissirostral, genus’ 
of this circle. .The truth, however, seems to be, that 
in very small groups like the present, the primary types | 
of nature do not show ai/ their own characters, but im=— 
part some one of them, as it were, to its neighboll Fr. 
