every instance in this bird, none being ligamentously attached 
to their fellows. The eighth and ninth pairs of ribs depend from 
the two anterior vertebrae of the svnsacrum. As wdl be noted, 
this arrangement of the ribs differs materially from that found 
in the nocturnal birds of prey. In the owl. the seventh pair of 
ribs articulate with the anterior synsacra! vertebra and their 
ossified costals are ligamentously joined to those of the pre¬ 
ceding pair. In such a widely divergent bird as the crake 
(“ Bprzana ") the costals of the eighth pair ligamentously join 
those of the seventh, while the ninth and tenth pairs of ribs 
are freely suspended from the two anterior vertebrae of the 
synsacrum. 
This question of the articulation of the ribs is one of some 
importance to the working Osteologist, and it is not too much 
to say that even in first-class Museums errors of pleural articula¬ 
tion are to be found. 
In the table of rib measurements hereunder given, : t should 
be specially noted that the ribs have been removed from the 
vertebrae, and each placed upon the measuring block, between 
two vertical lines, and the result thus obtained duly listed— 
First Pair of Ribs—26 111m. long, between vertical lines: 
distance between tubercula and capitula, 9 mm. 
Second Pair of Ribs—53 mm. long, between vertical lines: 
distance between tubercula and capitula, 10 mm. 
Third Pair of Ribs—64 mm. long, between vertical lines; 
distance between tubercula and capitula. 12 mm. 
These are the first ribs to reach the sternum, and the first 
also to develop epi-pleural processes. The ossified sternals are 
16 mm. long. The width across the ribs proper and the pro¬ 
cesses is 12 mm. in maximum measurement: the processes arise 
from the ribs at 14 mm. from their distal ends. As many as four 
pneumatic foramina penetrate the bone, while foramina of a 
similar kind pierce the sternal ribs at their distal ends. In some 
of the succeeding ribs the foramina become so numerous as to 
form a line of perforations down the rib surfaces upon the under 
side. 
Fourth Pair—Although these ribs have a greater curve 
than the last pair, and are more powerfully constructed, yet 
their length is exactly the same, viz., 64 mm., between vertical 
lines. The distance between capitula and tubercula (hereafter 
called “proximal articular widths’*) is 15 mm.: the lower edges 
of the epi-pleural processes are also 15 mm. from the distal ends. 
The greatest expanse across the ribs and processes, taken at the 
apices of the latter, is 21 mm. 
