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Show 34 ON THE ANATOMY OF CHRYSOCHLORIS TREVELYANI. [Jan. 15, triangular fibro-cartilage, the ulna is received into a facet formed by the cuneiform and pisiform, and this part of the wrist is shut off from the rest by an antero-posterior septum. In addition to this there is a partial septum which projects into the joint from the anterior ligament opposite the articulation between the scaphoid and semilunar bones. The hip-joint on disarticulation in both shows exactly the same arrangement that I have already described and figured in the Armadillo '. The ligamentum teres is present but is continuous along its lower border with the capsule, and the head of the femur shows a vertical notch for its reception instead of a pit. The knee-joint has all the characteristics of a generalized mammalian knee; the only characteristic thing about it is that the joint is bipartite owing to the great size of the ligamentum mucosum. As in the case of the Brocket Deer, the external condylo-tibial joint is shut out of the main cavity of the knee by the ligament which is attached behind to the crucial ligaments and in front to the origin of the extensor longus digitorum. The external lateral ligament is very strong, and passes from the condyle to the head of the fibula just behind the prominent anterior projection. The crucial ligaments and the semilunar cartilages are those of a generalized mammal. There are no tibio-fibular joints. As in most of the Insectivora, the two leg-bones are synostosed above and below. The ankle-joint is nearly a perfect hinge ; it consists of tibio-astragalar and fibulo-calcaneal portions. There is absolutely no posterior ligament, as the articular surfaces of the tibia and astragalus are continuous posteriorly with the cartilage-covered surfaces lining the broad groove in which the flexor fibularis tendon plays; this groove is continued on beneath the sustentaculum tali. There is no articular facet on the anterior border of the lower end of the tibia for articulation with the neck of the astragalus during dorsal flexion of the ankle. The external lateral ligament has, as usual in mammals, only two fasciculi; they correspond to the middle and posterior of human anatomy. The internal lateral ligament has the typical mammalian X-form, the more superficial fasciculus of the X running downward and forward to the navicular, the deeper running downward and backward to the astragalus. 1 Journal of Anat. vol. xxxiv. p. 305. |