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Show 1899.] THE MYOLOGY OF THE EDENTATA. 993 (2 7, 28). In the Manidce (29, 32, 33) the ilio-tibialis, tensor femoris, and ectogluteus form a continuous sheet as in the majority of mammals, but the ilio-tibialis is remarkable for the frequency with which it is wholly or partly inserted into the inner side of the patella. In the Orgcteropoclid.ee, 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- and entogluteus 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 condition. 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 Oryeteropus (35, 37) the entogluteus was present, but Humphry says that in his specimen (36) it was scarcely distinguishable from the mesogluteus. 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 Tamandua (14),Dasupus (22, 24), Chlamydophorus (28 a), and Oryeteropus (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 profundusand 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 Rapp (15). It is also mentioned in Tatusia (25) and Cholcepus (10), but it does not seem to be 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 interims and Gemelli.-Cuvier states in his ' Lecons,' " 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. W e found this arrangement existing throughout the Edentata, with the exception of the Orgcteropodidce, 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 extemus.-In the Braclgpodidce 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 |