MR. ST. G. MIVART ON THE ANATOMY OF ECHIDNA HYSTRIX. 397 
corresponds with the capitulum of the humerus; and the inner condyle of the femur 
corresponds with the trochlear of the humerus." 
At page 600 he calls attention to the embryonie condition of the limbs (with their 
flexor surfaces direeted inwards and their extensor surfaces outwards) and the sub- 
sequent opposite rotation of their long axes, the last cireumstance accounting for the fact 
that in the adult the posterior surface of the arm corresponds with the anterior surface of 
the leg. 
At page 601 he notices the similarity in position of the palm of the hand and sole of 
the foot, and aecounts for it by the rotation of the distal segment of the anterior limb in 
an opposite direction to that of its proximal segment. 
In his very valuable paper **On the Limbs of Vertebrate Animals," Dr. Humphry 
maintains substantially the same views, giving examples of the retention throughout life 
in many lower Vertebrata of the conditions transitorily presented by the limbs of the 
higher forms. He says, “It has already been remarked that the upper parts of the 
ilium and the scapula become inclined towards one another during development; and it 
is probable that they also participate, to some extent, in the rotation which the limbs 
undergo. "That is to say, that at first they are simple, straight, vertically placed ele- 
ments; and that the corresponding parts, viz. the hinder edge of the scapula and the 
anterior edge of the ilium, like the surfaces of the limbs of which they are a continuation, 
are originally directed more or less outwards, and subsequently become turned towards 
one another. I am not aware that any such change has been actually traced; but it is 
suggested by an examination of the parts, especially of the scapula, in MoNOTREMES, 
Birros, and REPTILEs. In the ORNITHORHYNCHUS, more particularly, the hinder edge of 
the seapula has an inclination outwards, and the spine is turned forwards and forms the 
anterior margin of the scapula. Such a theory of the rotation of the scapula on its ver- 
tical axis accords also with the mode in which, in Mammats, the clavicle and acromion 
usually eross over the coracoid process." i 
In his tables exhibiting the serial homologies of the bones, ligaments, muscles, arteries, 
and nerves of the limbs, the spine and acromion of the scapula are represented, at 
page 35, as corresponding with the ridge for the gluteus maximus continued into the 
sacro-seiatic ligament, the subacromial notch with the sacro-seiatie notch, the great 
tubercle of the humerus with the great trochanter of the femur, and the small tubercle 
of the humerus with the small trochanter of the femur. At page 37 it is stated that 
~ subscapularis represents the iliacus internus, and that the latissimus dorsi may re- 
present the psoas magnus. Dr. Humphry, at page 22, also argues against the theory of 
the “torsion of the humerus ” (supported by M. Charles Martins and others), yet, at 
page 35, he represents the outer condyle of the humerus as answering to the inner con- 
dyle of the femur, and vice versá. | 
Professor Huxley, in his Hunterian Course! of Lectures for the year 1864, after re- 
ue the principal conclusions arrived at by his predecessors, states that none of 
em can be considered thoroughly satisfactory, and that even what he himself proposes 
Cannot be so considered, on account ofits not having been checked by a study ofthe develop- 
* Reported in the * Medical Times’ for 1864, see p. 203. 
en 3K 
