Page:A descriptive catalogue of the Warren Anatomical Museum.djvu/143

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HEALTHY ANATOMY
121

body of the bone. It is formed, as it were, of two clavicles so turned that their upper surfaces are pressed against each other, and their greater concavities directed upwards. The scapula is composed of two bones, united at the glenoid cavity, having an acromion and spine on each side, but no coracoid processes. The bones of the arm, forearm, and hand are perfectly symmetrical; all the bones of the last two are arranged in a plane passing through the fœtus from before backwards, the radius in front and the ulna just behind it.

"The pelvis, as seen behind, has neither pubic nor ischiatic bones, but consists of two ilia, the left one of A and the right of B, united at the acetabulum, which last is on the median line. The femur is much compressed laterally, is slightly twisted, but otherwise symmetrical. The tibia and fibula are in the same plane with the arms, and each has a projecting point of bone, as if they had both been fractured. The tibia is the foremost of the two, and has a right and left tuberosity for the attachment of the right and left patella. The tarsal bones were not ossified, but the cartilage of a single os calcis was easily made out. The large and symmetrical toe had three phalanges, showing that it did not correspond with the great toe, contrary to what its great size would lead one to expect.

"Muscles.—Only such parts of the muscular system will require notice as are connected with the limbs described above, all the others being normal.

"The left sterno-mastoid of A and the right of B have the usual attachments to the head, but both are inserted into one and the same symmetrical clavicle and the single sternal piece above mentioned.

"The left sterno-hyoid and sterna-thyroid of A and the right ones of B arise from a common sternum, but are inserted into the usual parts belonging to the corresponding heads of the fœtus.

"The two trapezii, one arising from each head and vertebral column, are inserted into their respective portions of the compound scapula and clavicle.

"The levator anguli scapulæ and the rhomboidei are double.