. 
34 
Gluteus externus.—The external gluteus (gluteus medius of Meckel), 
as in most Mammalia, is smaller than the middle or internal glutez, 
but is relatively larger in the Apferyz than in birds of flight, in which 
it is described as the pyriformis by Cuvier. This muscle, however, 
besides its origin from the outside of the pelvis, overlaps part of the 
gluteus medius, and has its insertion into the femur at some distance 
below the great trochanter, all of which are marked characteristics 
of the gluteus magnus. Origin. It takes its origin from the superior 
margin of the os innominatum, extends along an inch and a quarter 
of that margin, directly above the hip-joint, and is chiefly attached 
by distinct short tendinous threads, which run down upon the exter- 
nal surface of the muscle: it rises also by carneous fibres from the 
external surface of the innominatum for three lines below the superior 
margin. Insertion. The fibres converge and pass into a tendinous 
sheet, beginning on the external surface of the muscle half-way down 
its course, which ends in a broad, flat, strong tendon, inserted into a 
rising on the outer side of the femur nearly an inch below the great 
trochanter. It abducts and raises the femur. 
Gluteus medius.—Origin. A large triangular, strong and thick 
muscle, has an origin of three inches extent from the rounded an- 
terior and superior margin of the ilium, and from the contiguous 
outer surface of the bone for an extent varying from an inch to eight 
lines. Jns. Its fibres converge toa strong, short, broad and flat ten- 
don, implanted in the external depression of the great trochanter, 
having a bursa mucosa interposed between the tendon and the bony 
elevation anterior to the depression. 
Gluteus minimus.—Origin. It rises below the preceding muscle 
from the anterior and inferior extremity, and from one inch and 
three-fourths of the inferior and outer margin of the ilium, and con- 
tiguous external surface, as far as the origin of the gluteus medius ; 
also by some fleshy fibres from the outside of the last rib. Ins. These 
fibres slightly converge as they pass backwards to terminate in a 
broad flat tendon which bends over the outer surface of the femur, to 
be inserted into the elevation anterior to the attachment of the gluteus 
magnus. 
A muscle which may be regarded either as distinct, or a strip of 
the preceding one, arises immediately behind it from half an inch of 
the outer and inferior part of the ilium ; its fibres run nearly parallel 
with those of the gluteus minimus, and terminate in a thin flat 
tendon, which similarly bends round the outer part of the femur, to 
be inserted into the outer and under part of the trochanter imme- 
diately below the tendon of the gluteus medius. ‘This muscle is 
peculiar to the Apteryx, and the preceding portion, or gluteus mini- 
mus, is absent in most birds. 
Use.—All the preceding muscles combine to draw the femur for- 
wards, and to abduct and rotate it inwards. 
Iliacus internus.—This is a somewhat short thick muscle, of a pa- 
rallelogrammic form, fleshy throughout; rising from the tuberosity 
of the innominatum in front of the acetabulum immediately below the 
gluteus minimus, and inserted at a point corresponding to the inner 
