50 A NATURAL HISTORY OF THE CUCKOO. 
complication of structure ; but in the genera we are now describing it 
is always met with, more or less varying from a nearly simple line, 
in some Goniatites, to the extreme of complication in the Ammonites 
of more recent formations. 
The approximation to the Nautilus, denoted by the nature of 
the septum, is the separation most to be depended on in the group 
which has received the name Goniatites, a name derived from the 
Greek ys, an angle, and pointing out the usual appearance of the 
intersection, consisting of a succession of small curves meeting in 
angles which, along the back of the shell, always point in the direc- 
tion opposite the aperture. Most of the species are in some measure 
rounded, and often the last whorl envelopes the rest ; indeed, alto- 
gether their general appearance more resembles the early forms 
of Nautilus than any Ammonites ; but their siphuncle, which usually 
is extremely small and thread-like, is always situated on the dorsal 
margin, or, in other words, runs along the back or outside of the 
whorls. It is supposed, also, that the proportional magnitude of the 
last chamber was much greater in this group than in other Ammon- 
ites, so large a portion as one turn and a half being sometimes left 
vacant for the habitation of the animal. 
( To be continued. ) 
A NATURAL HISTORY OF THE CUCKOO,* 
(cUCULUS CANORUS). 
By Epwarp BrytuH, Esq. 
Tue subject proposed for dissertation is the Natural History 
of the Cuckoo, concerning which extraordinary British bird it will 
be admitted that too many elucidations cannot be adduced; for 
which reason I purpose to enter somewhat minutely into the seve- 
ral details. 
There are many who have lived long in the country without 
ever having seen the Cuckoo ; and the poets have sometimes figured 
* Read before the Ornithological Society of London, July 6th, 1838. 
