1903. ] OSTEOLOGY OF THE CUCULIFORMES. 273 
The most complete synsacrum is that of Coua, and is made up 
as follows :—1 thoracic, 3 lumbar, 3 lumbo-sacral, 2 sacral, and 
4 caudal, making 13 in all. 
Rhopodytes seems to possess the most reduced synsacrum : the 
number of thoracic, lumbar, and sacral is the same as in Couwa, but 
the lumbo-sacrals are reduced to 1 and the caudal to 2: making 
therefore a total of 9 vertebra as against 13 in Coua. 
Crotophaga and Geocoecyx each have 11 vertebrae in this region. 
In the former, the reduction is from the lumbo-sacrals, which are 
only represented by a single vertebra; in the latter there are 
2 lumbo-sacrals, but only 3 caudals. 
In other genera, the number of vertebrie appears constantly to be 
12, composed as follows :—1 thoracic, 4 lumbar, 1 lumbo-sacral, 
2 sacral, and 4 caudal. 
In no case can distinct sacral vertebre be made out. The 
synsacrum of Rhamphococeyx 1s vemarkable in that the single lumbo- 
sacral vertebra bears a pair of exceptionally strong ventri-lateral 
processes. Vestiges of these appear in Seythrops, Coua, and 
Taccocoua. 
In Centropus the third and fourth pairs of ventri-lateral processes 
are apparently undergoing coalescence. In some skeletons this 
fusion is complete; in others traces, more or less marked, of the 
original buttresses still remain. 
The last two caudal vertebra: combine to form a well-marked 
planum anale. 
There are 6 or 7 post-synsacrals—free caudal vertebra. Of these 
the 4th and 6th bear pointed intercentra, which, however, are 
completely fused with thew respective centra. 
The total number of vertebre reaches its highest in Coua 
with 37. 
The vertebral column of the Musophagi is scarcely distinguish- 
able from that of the Cuculi. 
The cervical vertebree closely recall those of Cuculus. They may 
be distinguished therefrom, however, apart from their greater size, 
in that the 3rd and 4th both send backwards a bar from the meta- 
to the hyperapophysis, and in that the 7th and 8th send back a 
similar bar from the same region to the middle of the neural arch. 
There are only two cervico-thoracies. The vertebra corresponding 
to the third cervico-thoracic of certain Cuckoos, e.g. Scythrops, 
becomes in the Musophagi thoracic, being joined to the sternum by 
a sternal rib. The thoracic vertebre differ from those of the 
Cuckoos, in that the transverse processes send backwards from their 
postero-external angles a long bony spike to overlap the transverse 
process of the vertebra next behind it. These connecting-rods 
are either wanting or very feebly developed in the Cuckoos, e. g. 
Seythrops. 
The cervical vertebr are 12 in number, the cervico-thoracic 2, 
thoracic 6, the last being fused with the synsacrum. 
The synsacrum contains 13 vertebre, and is made up as 
follows: thoracic 1, lumbar 3, Iumbo-sacral 3, sacral 2, caudal 4, 
tS 
