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Show 1890.] HELODERMA SUSPECTUM. 181 and fleshy, although laterally compressed, and at first passing directly forwards, soon turns outwards, and becoming tendinous is inserted into the trochanter major of the femur of the same side. Before arriving at this insertion, the femoro-caudal throws off another tendon, which, passing down through certain other muscles of the thigh, is inserted into the hinder surface of the interarticular cartilage between the tibia and the femur. Professor Mivart found this second tendon of insertion likewise present in Iguana. 70. The Ischio-caudal muscle arises from the outer aspect of the chevron-bone of the eleventh caudal vertebra, counting from the sacrum, and, ensheathed in the fat that is surrounded by the infero-caudal of the same side, it passes directly forwards, as a sub-cylindrical, muscular cord of some size; running close to the vertebrae, it becomes bulbous just before arriving at the vent, and dipping down, and passing forward between the two layers of the cloacal muscle, is finally inserted into the tuberosity of the ischium. 71. Cloacal muscle.-This arises, almost carneous, from the ventral surfaces of the diapophyses of the fourth and fifth caudal vertebrae, and passing downwards and forwards as a moderately thin sheet of muscle it becomes inserted along upon the upper surface of the cloaca from its posterior lip forwards. As already stated above, the ischio-caudal passes between its layers on its way to its insertion. This cloacal muscle is situated to the outer side of the femoro-caudal, and internal to the infra-caudal. 72. Transversus perinei.-Superficial to all the muscles here described, and stretching transversely across the region just posterior to the cloaca, we find a thin muscular layer faintly divided into two by a median, longitudinal line. Either lateral half of this represents one of the present muscles, a transversus perinei. For the most part it is attached to the post-cloacal fascia of the region in question. (From this point onwards we resume our descriptions of the muscles of the trunk.) 73. Rectus abdominis.-Arising from the xiphoidal extremity of the sternum, and from the costal rib that there articulates, either rectus abdominis passes down the entire length of the body to the anterior pelvic region, being throughout its course intimately united with its fellow of the opposite side. Posteriorly it becomes inserted into the ischio-pubic ligament and the neighbouring fascia. 74. Pgramidalis.-This muscle is formed by a strong triangular slip thrown off by the rectus abdominis just above the insertion of the latter. Its fibres converge, and passing outwards and slightly backwards they are inserted, upon either side, into the " hamular process" of the pubis. Sanders found this muscle present in Liolepis, but he does not award it a separate description (P. Z. S. 1872, p. 161). 75. Obliquus abdominis externus.-This broad and powerful sheet of muscle here arises by an anterior expansion from the inner surface of the skin overlying the chest; by means of strong digita-tions from all of the dorsal ribs, and from six or seven of the abdominal ribs that follow them ; and, finally, by far less distinctly |