1004 MESSRS. B. V. A. WIXDLE AXD F. G. PARSONS ON [DeC. 19, 



GaMroenemius. — This muscle, amongst the Edentata, has, with 

 certain exceptions, the typical mammalian arrangement. In the 

 Bradypodidcp rhe two heads do not unite until they reach the cal- 

 caneum, but they are not twisted in such a way that the inner 

 becomes superficial and then external {cf. Journal of Anat. & Phys. 

 vol. xxviii. p. 414). This is true of Bradijpus (1, 2) and Choloei^ug 

 (8, 9, 10). In the Manidce (29, 32, 33) the external head is very 

 large and rises a long way up the shaft of the femur — a condition 

 far exceeding anything which we have hitherto observed in any 

 other mammal. It is interesting to notice that nearly all observers 

 have recorded the absence of fabeilae except in the Orycteropodklte. 



Soleus. — Among the Bradypodida the soleus often rises quite 

 low down on the fibula in Bradypnis, in which animal it arose in 

 one case (5) from the middle, and in another (1) from the lower 

 third of the bone. It is inserted into the calcaneum without 

 joining the tendo Achillis (1, 2). In Choloeptis the chief insertion 

 is also into the calcaneum in front of the tendo Achillis, but 

 Humphry noticed that some of its fibres were continuous with 

 those of the accessorius. Among the Myrmecopliagida; its origin 

 was chiefly from the fascia over the deep flexor muscles in 

 Myrmecophacia (11) '. In the last-mentioned animal, in Tamandua 

 (14), and in Ci/chthainis (19, 20) it is inserted hs in the Bradypodidce. 

 In the Dasypodidcp it seems usually to join the outer head of the 

 gastrocnemius, but our information is not very clear upon this point. 

 lu the Manidcp (29, 32) and Orycteropod'uUe (35, 36) its insertion 

 is as in the Bradypodidce and Myrmecopliagida. It will thus be 

 seen that the Edentata as an order are characterized by the 

 separate insertion of the soleus and the absence or incompleteness 

 of the tendo Achillis. 



Phntarw. — This muscle is liable to a good deal of variation in 

 the Edentata, and is likely to be confused, on the one hand, with 

 the femoral head of the flexor cruris lateralis (biceps), and, on the 

 other, ^vith the flexor tibialis and fibularis. In the Bradypodidce 

 the muscle was absent in one specimen (1), but in three others (2, 

 4, 5) it was present as a very large muscle which rose from above 

 the external condyle of the femur, and was inserted into the long 

 flexor tendons in the sole of the foot. It is described by some 

 writers as an extra head of the long flexors of the toes. In 

 ChoJcepxis (8, 9, 10) the muscle is absent, but the condition in this 

 form will be again referred to under the head of the tibialis posticus. 

 Among the MyrmecoplwgidcKit is present in Myrmecophaya (11) and 

 has the usual mammalian insertion into the plantar fascia. In 

 Cydothurus (17, 19, 20) it is also present, and is inserted into the 

 elongated ossicle on the tibial side of the foot. This insertion is 

 interesting when compared with that which is found in the hand 

 of Pedetes {cf. Proc. Zool. See. 1898, p. 867), in which the palmaris 

 iongus, the serial homologue of the plantaris, is inserted into the 



' In (12) it had the generalized niammaUan origin from the back of tlie head 

 of the fibula. 



