en Carrier | 2.80 | 0.17 | German Pouter | 2.36 | 0.54 |
| Dragon | 2.45 | 0.41 | Jacobin | 2.33 | 0.22 |
| Carrier | 2.75 | 0.35 | English Frill-back| 2.40 | 0.43 |
| Short-faced Tumbler| 2.05 | 0.28 | Swallow | 2.45 | 0.17 |
+--------------------+-------+-------+-------------------+-------+------+

{175}

This table shows that in these twelve breeds the sternum is on an
average one-third of an inch (exactly .332) shorter than in the
rock-pigeon, proportionally with the size of their bodies; so that the
sternum has been reduced by between one-seventh and one-eighth of its
entire length; and this is a considerable reduction.

I have also measured in twenty-one birds, including the above dozen,
the prominence of the crest of the sternum relatively to its length,
independently of the size of the body. In two of the twenty-one birds
the crest was prominent in the same relative degree as in the
rock-pigeon; in seven it was more prominent; but in five out of these
seven, namely, in a fantail, two scanderoons, and two English carriers,
this greater prominence may to a certain extent be explained, as a
prominent breast is admired and selected by fanciers; in the remaining
twelve birds the prominence was less. Hence it follows that the crest
exhibits a slight, though uncertain, tendency to become reduced in
prominence in a greater degree than does the length of the sternum
relatively to the size of body, in comparison with the rock-pigeon.

I have measured the length of the scapula in nine different large and
small-sized breeds, and in all the scapula is proportionally shorter
(taking the same standard as before) than in the wild rock-pigeon. The
reduction in length on an average is very nearly one-fifth of an inch,
or about one-ninth of the length of the scapula in the rock-pigeon.

The arms of the furcula in all the specimens which I compared, diverged
less, proportionally with the size of body, than in the rock-pigeon;
and the whole furcula was proportionally shorter. Thus in a runt, which
measured from tip to tip of wings 381/2 inches, the furcula was only a
very little longer (with the arms hardly more divergent) than in a
rock-pigeon which measured from tip to tip 261/2 inches. In a barb, which
in all its measurements was a little larger th