OCR Text |
Show 1002 MESSRS. B. C A. WINDLE AND F. G. PARSONS ON [Dec. 19, outer. In the Dasypodidce the origin is always tarsal (calcaneal with occasional additional slips). In Dasypus (22, 24) the insertion was into the second, third, and fourth digits, though in another specimen (23) into the first, second, and third. In Tatusia- (25) its insertion was into the second, third, and fourth toes, while in Chlamydophorus it was inserted into the four outer toes. In the Maniotce the fibular origin sometimes occurs as in Bradypus, at least this was the case in our specimen (29), though in Humphry's (32) it came from the tarsus. The insertion may be into the four outer toes (32, and apparently 34), or into all of them (29). In the Orycteropodidce (35, 36) the muscle rises from the calcaneum, and is inserted in one (37) into the three inner toes, in another (36) into the three middle toes. Peroneus longus.-In the Bradypodidce this muscle was found in three specimens of Bradypus (2, 4, 5) rising from the condyle of the femur and upper part of the fibula, its insertion in all cases being into the base of the outermost metatarsal bone. In our specimen of Bradypus (1) we failed to find any peroneus longus at all, aud it is absent in Cuvier and Laurillard's plate (6). In Cholcepus (8, 9, 10) the muscle only rises from the upper part of the fibula aud is inserted into the base of the outermost metatarsal bone ; so that in the family of the Bradypodidce we think we are able definitely to state that the peroneus longus tendon never runs across the sole of the foot. Among the Myrmecophagidae, the muscle rises from the tibia and fibula in Myrmecophaga (11), from the fibula and semilunar cartilage in Tamadua (14), and from the fibula only in Cyclothurus (17). In no member of this family has a femoral head been found. The tendon always runs across the sole and is inserted into the innermost metatarsal bone or bones, into the entocuneiform, or (20) into the navicular. Among the Dasypodidce the muscle has patellar and fibular origins in Dasypus (22) * and Tatusia (25), but only fibular in Chlamydophorus (27, 28). In another specimen (28 a) of this animal there was an additional origin from the patella. In all these animals the tendon passes across the sole of the foot. In the Manidce (29, 32, 33) the muscle rises from the fibula and passes across tbe sole of the foot. In the Orycteropodidce. there is no definite femoral origin, but the peroneus longus rises from the external lateral ligament and semilunar cartilage as well as from the upper part of the fibula. The tendon passes across the sole to the first metatarsal bone. In those animals, such as the Bradypodidce and Dasypodidce, which have a femoral origin for the peroneus longus, there is a distinct external lateral ligament in addition. This fact is of considerable importance in arriving at a conclusion with regard to the morphology of that ligament. Peroneus brevis.-In the Bradypodidce this muscle was present in three specimens (2, 4, 5), but was absent in the fourth (1). It rose from the lower part of the fibula and was inserted into the 1 This was also seen in another dissection at the Royal College of Surgeons. |