10IJ2 MESSRS. B, C. A, WIXDLB X^D E. G. IMRSONS ON [DeC. L9, 



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 

 Manidce 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 OryGteropodid(B (35, 36) the muscle rises from the calcaneum, 

 and is inserted in one (37) into the three inner toes, in another 

 (36) into the thi-ee 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, and 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 and 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 peroueus longus tendon never runs 

 across the sole of the foot. Among the Myrmecop>hagidce, 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 Gyclothurus (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 innerujost 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 Chlamydo- 

 pliorus (27, 28). In another specimen (28 a) of this aniiual 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 the 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 meta- 

 tarsal bone. In those animals, such as the Bradypodidce and 

 Dasypodidoi, 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, o), but was absent in the fourth (1). It 

 rose from the lower part of the fibula and was inserted into the 



^ This was also seen iu another dissection at the Eoyal College of Surgeons. 



