The =levatores costarum= number ten or eleven pairs.
The =diaphragm= presents several important differential features. Its
slope is much steeper and its width is greater than in the horse. The
costal attachment extends almost in a straight line from the upper
fourth of the last rib to the junction of the eighth rib with its
cartilage, and along the latter to the sternum. The mid-line slopes from
the twelfth thoracic vertebra obliquely as far as the vena cava, beyond
which it is almost vertical. The right crus divides into two branches,
which circumscribe the œsophageal opening, unite below, and then spread
out in the tendinous center. The left crus is small. The œsophageal
opening is situated about four to five inches (10 to 12 cm.) below the
eighth thoracic vertebra, a little to the left of the median plane. The
foramen venæ cavæ is a little more ventral and almost in the median
plane. The other muscles resemble those of the horse.