278 MR. W. P. PYCRAFT ON THE [ Mar. 17, 
posteriorly than in Schizorhis. The sternal notches of Z'wracus, 
it is to be noted, though preserving the same relative proportions 
between themselves, are yet relatively shallower than in Schizo- 
rhis with regard to their relation to the corpus sterni. 
There is a well-developed spina externa, but no trace of a spina 
interna. In Schizorhis the spina is flabellate and projects from a 
rounded base. In Zuracus it is quadrate in form. In 7’. buffoni 
it projects nearly as far forwards as the antero-ventral angle of 
the carina, and is distinguishable from the anterior border of the 
carina only through the medium of a notch. Were this notch 
filled up, the spina would disappear and the anterior border of 
the keel would present a vertical face projecting Hae beyond the 
coracoid grooves, as in certain Coraciiform birds, e. g. Cyanops. 
The .coracoid grooves overlap one another. The dorsal lip 1 1s 
extensive. <A median notch oceupies the place of the spina 
interna, and this is bounded on either side by a conspicuous 
oblong glenoid surface, which articulates with a special facet on 
the coracoid. In the Cuckoos the dorsal lip does not overhang 
the ventral, the coracoid grooves do not overlap nor in some 
cases even reach the middle line, and the oblong articular facet 
on the dorsal lip for articulation of the coracoid is only slightly 
developed. In the Musophagi the dorsal surface of the base a 
the spina externa affords articulation for the right coracoid ; 
the Cuckoos this is never the case. 
In the Musophagi the articular surfaces for the ribs are fairly 
widely spaced, less so in Z'uracus ; in the Cuckoos these surfaces 
are crowded together. 
The coracoid in the Cuculi is relatively long and slender, being 
nearly or quite as long as the sternum. From the ventral aspect, 
one of the most conspicuous features is the large procoracoid. 
This forms a large oblong shelf projecting inwards and downwards 
from the shaft, at about the level of a line drawn across the shaft 
from behind the glenoid cavity. The acrocoracoid is large, and 
not twisted on the shaft so as to conceal the foramen interosseum. 
The processus lateralis is well developed and the foramen swpra- 
coracoideum is absent. 
The processus lateralis basalis may be either broad and quad- 
rate, with its antero-external angle produced forwards into a 
spine, as in Cuculus, Rhopodytes, Hudynamys, Taccocoua, Rham- 
phococcyx, Scythrops, and Guira ; or narrow and directed outwards 
and backwards, as in Centropus, Cowa, and Dromococcyx. In 
Taccocoua, and to a less marked extent in Centropus, the impres- 
sion for the sterno-coracoideus muscle, on the dorsal aspect of 
the coracoid, is bounded in front by a sharp vertically directed 
spine. 
The scapula is long and narrow, and differs somewhat in shape 
in the different genera; but the variations are unimportant, and 
not sufficiently large to justify description here. The acromion is 
short and stout, save in Cowa reynaudi, wherein it is reduced in 
width to form a somewhat cylindrical process. 
