REPORT ON THE SEALS. 223 



cartilages. The last digitation also has origin from the lumbar fascia; the direction of the fibres is 

 much the same as in Phoca. As most of the aponeuroses of the trunk had lost distinctness owing to 

 the length of time the specimen had been in salt, I cannot enter into a description. From 

 the last digitation the fibres pass directly backwards and reach the ventral anterior spine of the ilium, 

 and are attached to it. The mesial fibres terminate upon the middle of the rectus muscle in the 

 anterior two-thirds, and upon its inner edge in the posterior third. From the ventral anterior 

 spine of the ilium the insertion remains muscular until it reaches the pectineal eminence, where it 

 becomes tendinous, and is inserted into the pelvic brim, reaching the outer side of the rectus abdominis 

 and forming the outer pillar of the external abdominal ring. The rest of this aponeurosis crosses 

 over the cord and terminates upon the origin of the rectus. The five anterior slips interdigitate with 

 the serratus magnus, the sixth, seventh, and eighth with the latissimus dorsi. 



The Obliquus interims abdominis in Phoca vitulina is hidden by the external oblique, and has 

 a slight resemblance to a quadrilateral figure. It arises by muscular fibres from the ventral border 

 of the ventral anterior spine of the ilium to the inner side of the origin of the sartorius ; from the 

 brim of the pelvis by muscular fibres from the front of the attachment of the inner pillar of the 

 external abdominal ring to the posterior part of the pectineal eminence ; from the lumbar fascia 

 between the last rib and the crest of the ilium by an aponeurosis; from the inner surfaces and tips of 

 the cartilages of the 13th, 14th, and 15th ribs; and from the adjacent sides of the 11th and 12th ribs 

 an inch from their terminations. The fibres of the muscle midway between the anterior ventral 

 spine of the ilium and the last rib are almost all transverse ; anterior to this they are directed 

 upwards and inwards, and anteriorly end opposite the posterior end of the xiphisternum. The fibres 

 are grouped into bands which are closely united, and between these bands the arterial supply for 

 the abdominal walls penetrates. The muscle ends anteriorly and mesially as an aponeurosis and by 

 fibres along its dorsal border ; the anterior part of the aponeurosis crosses over the posterior half 

 of the xiphisternum, and is inserted into the side of its anterior half and into the cartilages of 

 the 10th and 11th ribs. The two strong broad anterior bands, arising from the lumbar fascia 

 between which the transversalis partially arises, are inserted into the posterior border of the last 

 rib, and into the inner surface and tips of the cartilages of the 13th, 14th, and 15th ribs, and by 

 muscular fibres into the inner surfaces only of the 11th and 12th ribs. Behind the ensiform 

 cartilage and anterior to the level of the 14th rib the tendinous termination passes behind the 

 rectus and unites with the internal oblique of the other side ; posterior to this and anterior to the 

 posterior seventh of the rectus, the tendon passes over the rectus, and unites with the tendon of 

 the external oblique above it ; and at the posterior seventh of the rectus the muscle ends upon 

 the rectus by small muscular digitations. The posterior border of the muscle crosses over from the 

 anterior ventral spine of the ilium to the outer pillar of the external oblique, crossing the middle of 

 the thigh ; and the fibres rising from the brim of the pelvis turn outwards upon the thigh, and then 

 curve to the middle line. The most posterior fibres turn over the cord and are attached to its 

 outer fourth ; and four fasciculi descend upon the testicle, and form the cremastcr, being prolonged 

 from the inner and curved side of the fibres which arch over the cord. 



In Arctocephalus it arises by muscular fibres from the pelvic brim, beginning midway between 

 the symphysis and the pectineal eminence; the fibres between the anterior part of the pectineal 

 eminence and the anterior ventral spine of the ilium arise from the transversalis fascia ; between 

 this spine and the last rib the fibres anterior to the 4th lumbar spine spring from the lumbar fascia ; 



