the Family of Cuci ilidce. 435 
cuckoos, indeed, which have thus been detached, have altogether the 
appearance of belonging to a different type than those of the genus 
Cuculus ; and this idea is strengthened, when we find there are al- 
ready four or five species, all distinguished at first sight by their 
diminutive size, and their beautiful golden-green plumage. On 
the other hand, their actual structure is so completely that of an 
European group, that I must beg to be understood as being by no 
means satisfied on the propriety of the separation. For the present, 
however, I shall adopt this genus, conceiving that these splendid 
little birds may probably constitute the tenuirostral type of the 
Cucullnce, in which case they will be analogous to the humming- 
birds, and nearly all those genera whose plumage is ornamented 
with metallic colours. The attempt that has been made to define 
the group by its bill, nostrils, &c. as distinct from the cuckoos, is 
singularly unsuccessful ; while those light shades of difference really 
existing between Chalciies and Cuculu.i have been completely over- 
looked. Chalciiet, in fact, has the bill, nostrils, feet, and wings of 
Cuculus, with this difference only, that the tip of the upper man- 
dible is without the slightest indication of a notch : the second and 
third quill are longer than the fourth, and the feathers of the rump 
and upper tail-covers, instead of being thick-set and rigid, are of the 
same degree of density and softness as in ordinary birds. We have 
seen, that, however dissimilar in their appearance the foregoing 
groups of the Cuculince may be, yet that the variation of their ex- 
ternal structure is but slight. This consideration has much weight 
with me in the temporary adoption of M. Lesson's genus Chalciies, 
for we have just seen an example, in Erythrophrys, where there is 
an equally slight variation in external form, yet a most important 
one in economy and internal organization. 
The genus Eudynamy* of MM. Horsefield and Vigors rests on 
a much better foundation than the last. It is at once distinguish- 
ed from Cuculus by a stronger and thicker bill, the under mandi- 
ble of which is not only destitute of any curve, but has a decided 
angle at the under ridge. The feet are also proportionably strong, 
and are the most robust of all those groups we have yet noticed : 
the tarsus is longer, and almost naked, while the rump feathers are 
short and soft. In other respects, such as the wing, nostrils, and 
tail, this genus agrees with Cuculus. The nostrils, however, judg- 
ing from dried specimens, appear to be more oval than round. The 
great size of the bill in this genus induces me to think it is that 
which represents the Toucans, in which case it will be a fissirostral 
type. 
All the Cuckoos I have yet seen, with more or less pointed 
