420 MR. A. SANDERS ON THE [June 9, 
vertebra, and from the furrow between the zygapophyses and trans- 
verse processes of the two following vertebrae. It is inserted into 
the lower border and external end of the exoccipital. 
Cervicalis ascendens is the continuation forward of the sacro-lum- 
balis. It also arises from the surface of the second and third cervical 
ribs, and is inserted into the transverse process of the first cervical 
vertebra and basioccipital above the insertion of the longus colli. 
Sacro-lumbalis arises from the posterior extremity of the ilium, 
and is attached to all the ribs between the points corresponding to 
the angles and the insertion of the longissimus dorsi. 
Longissimus dorsi begins at the transverse process of the fifth 
caudal vertebra, interdigitating with the first caudal muscle; it has 
an attachment to the posterior end of the ilium, and is inserted into 
the bases of all the ribs between the last muscle and the zygapophyses 
of the vertebree as far forward as the fourth cervical. 
Spinalis dorsi commences between the inner point of the first caudal 
muscle and the neural spine of the fifth caudal vertebra, and is inserted 
into the neural spines of all the vertebra as far as the fourth cervical, 
occupying the space between the neural spines and the zygapo- 
physes; a small slip is continued forward beyond the fourth cer- 
vical, attached to the neurapophyses of the three anterior cervical 
vertebree. 
Rectus posticus arises from the neural spines of the second, third, 
and fourth cervical vertebrze ; it is directed outwards, and is inserted 
into the upper and inner surface of the exoccipital, within and above 
the trachelo-mastoid. 
Rectus anticus major arises from the point of the external apo- 
physis of the basioccipital, and is inserted into the hypapophysis 
and side of centrum of the first cervical vertebra, and in the same 
way into the rest as far as the sixth, and into the side of the cen- 
trum of the seventh. 
Scealenus arises from the side of the centrum of the second cervical 
vertebra dorsad of the last muscle, and is inserted into the cervical 
ribs from the first to the fifth, enclosing them in a triangular mus- 
cular mass, also into the sides of the bodies of the vertebrze belonging 
to these ribs; behind it is continuous with the intercostals. 
Rectus abdominis arises behind from a tendinous arch extending 
from the hook-like process of the pubis in front of the femoro-pelvic 
articulation to the ischium, which might be called ischio-pubic 
ligament, and is inserted by means of a fibrous membrane into the 
posterior extremity of the xiphisternum, and into the cartilage of 
the sixth sternal rib. It has six tendinous intersections running 
transversely across its fibres and occupying the whole thickness of 
the muscle. An offshoot is given off just beyond the most posterior 
intersection, which goes to be inserted into the hook-like process of 
the pubis; this appears to represent the pyramidalis. 
External oblique arises by fourteen digitations, each loosely at- 
tached to a rib at the external edge of the sacro-lumbalis ; the first 
digitation belongs to the seventh cervical vertebra, towards the 
middle line ; it is inserted behind to the hook-like process of the 
