1899.] THE MYOLOGY OF THE EDENTATA. 993 



( 27, 28). In the Manidce (29, 32, 33) tbe ilio-tibialis, tensor fasci* 

 femoris, and ectogluteus form a continuous sheet as in the majority 

 of mammals, but the ilio-tibiaHs is remarkable for the frequency 

 with which it is wholly or partly inserted into the inner side of the 

 patella. In the Orycteropodidce, Galton (35) describes the ilio- 

 tibialis as arising from the ilio-pectineal tubercle, and Humphry 

 (36) as coming from the last rib just external to the psoas. 



Mesogluteus, Entogluteus, and Pyriformis. — The Edentata are 

 remarkable for the imperfect differentiation of the meso- aud ento- 

 gluteus and the pyriformis, which three muscles form a large fleshy 

 mass. Such being the case, it is not surprising that the literature of 

 the subject presents-us with very varying accounts of their coudition. 

 The fleshy mass above mentioned has the usual origin from the 

 outer surface of the ilium and from the fascia which also gives 

 origin to the ectogluteus. In Bradypus (1) and Dasypus (22) we 

 separated a small entogluteus with some difficulty ; it was inserted 

 as usual into the front of the great trochanter. In Orycteropus 

 (35, 37) the entogluteus was present, but Humphry says that in 

 his specimen (36) it was scarcely distinguishable from the meso- 

 gluteus. The pyriformis is generally discernible in Bradypus 

 (1, 4, 5, 6) and Cholcepus (8, 10), rising, as usual, from the inside of 

 the pelvis. In 2\imaiidua (14), Dasypus (22, 2i), Ghlamydophorus 

 (28 a), and Orycteropus (35, 36, 37) it was also clearly made out. 

 In all the other forms of which we have records it is described as 

 absent or inseparable from the mesogluteus. 



Gluteus 2J^'of undus and ventralis.^ A gluteus ventralis (g. quartus) 

 was found in Tamandua coming from the whole ventral border of 

 the ilium. This is probably the third gluteal described by Kapp 

 (15). It is also meutioned iu Tatasia (25) and Oholcepus (10), but 

 it does not seem to \>e clearly differentiated with any frequency 

 in the order. The gluteus profundus (g. quintus) has, so far as we 

 have been able to ascertain, never been seen in Edentates. 



Obturator ititernus and Gemdli. — -Cuvier states in his ' Lemons,' 

 " that, in animals which have the ischium ankylosed to the 

 sacrum, a muscle coming from the external face of the ischium 

 takes the place of the obturator internus and gemelli." This, in 

 our opinion, is equivalent to saying that the intrapelvic portion of 

 the obturator internus is absent. We found this arrangement 

 existing throughout the Edentata, with the exception of the 

 Orycteropodidce, in which the typical mammalian arrangement 

 occurs, both gemelli and the obturator internus being recorded as 

 present (35, 36). In one case, however, Galton (35) states that 

 the anterior gemellus was double, one being attached as usual, the 

 other coming from the posterior half of the sacral edge of the 

 great sacro-sciatic foramen ; it seems possible that this so-called 

 second gemellus may really have been a pyriformis. 



Obturator externus. — In the Bradypodidce this muscle was present 

 and possessed the usual attachments in Bradypus (1, 2, 4) and 

 Cholcepus (8); but in a second specimen of the latter (10) it is 

 described as double, the upper part coming from the horizontal 



