REPORT ON THE SEALS. 183 



the fibres of the vastus externus near the patella. In Plwca hispida it arises from the outer surface 

 of the ilium ventral to the ridge between the ventral anterior spine and the middle of the anterior 

 rim of the acetabulum. It does not arise from the ventral border, for the representative of the 

 iliacus comes from the ventral posterior spine. It is inserted into the upper edge of the patella 

 and is also joined above its insertion by a few fibres of the external vastus. In Phoca barbata it 

 arises from the fossa of the posterior third of the outer surface of the ilium ; and from the capsule 

 of the hip-joint, but not from the anterior border of the ventral surface. It is inserted into the 

 upper edge of the patella, and is also united to the fibres of the vastus externus near the insertion. 



In Macrorhinus Iconinus it arises from the external surface of the ilium, to the ventral side of 

 the ridge running from the outer side of the ventral anterior spine to the middle of the 

 acetabulum. Where the ridge is covered by the capsule it takes origin from it, and arises also 

 from the outer half of the ventral surface of the ilium dorsal to the origin of the iliacus. Above 

 the patella it forms a broad flat tendon, which is joined on its dorsal side above the patella by 

 fibres of the external rectus, and is inserted into the upper edge of the patella. 



In Arctocephalus gazella it arises from the external surface of the ilium ; and from the capsule 

 covering the front of the acetabulum. If a straight line be drawn from the ventral anterior 

 spine to the middle of the anterior rim of the acetabulum, a triangular surface is mapped out, 

 which is bounded ventrally by the ventral posterior spine, posteriorly by the rim of the 

 acetabulum, on the inner side by the outer edge of the brim of the pelvis ; and dorsally by the 

 line from the ventral posterior spine to the acetabulum. Within this space is the origin of the 

 muscle. It is inserted into the upper edge of the patella, and is joined on its outer side near the 

 insertion by fibres from the vastus externus. Lucae has it as united to the cruralis, but I found it 

 blended with the vastus externus. It is similar hi Otaria and Tricheehus. 



As it is the reflected tendon in human anatomy that acts mostly upon the thigh, and this is 

 the origin in the Seals corresponding to it, it is probably only a flexor of the thigh. It is 

 relatively a much larger muscle than in human anatomy and will compensate for the vastus internus. 

 In the Phocinaj it is supplied by the anterior crural nerve. 



The Vastus externus in the Phocinffi and Macrorhinus Iconinus is best seen in the last named 

 animal, and extends along the outer border of the femur to the epiphysial line of the external 

 condyle ; i.e., to the supracondyloid ridge, and is similar in all. It is placed upon the crureus 

 and covers a considerable part of it ; it arises from the capsule surrounding the neck of the femur, 

 from the shaft between the inner termination of the great trochanter on the neck, from the whole 

 length of the anterior edge of the great trochanter, slightly from the shaft below this, and from 

 the external border of the femur in its upper half. It is blended with the crureus and is 

 inserted into the upper and outer half of the patella, and into the capsule of the knee-joint, on a 

 level with the middle of the outer edge of the patella. No fibres descend further down the capsule. 



In Arctocephalus gazella it is a rectangular muscle, lying to the outer side of the rectus femoris, 

 and partially overlapping the crureus. It arises from the front surface of the femur below the 

 great trochanter; from the front of the neck of the same; from the capsule of the hip-joint, and 

 from the external border of the shaft, almost reaching the external condyle. It is inserted into the 

 outer upper half of the patella, and blends with the rectus femoris. Lucae describes a combined 

 crureus and vastus externus. In Otaria it is attached to the whole anterior surface of the femur, as 

 also in Tricheehus. 



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