o/'Bradypus tridactylus. 63 



the sacrum, and is inserted into the outer part of the femur, 

 immediately below the great trochanter. It is much smaller 

 than its homologue in the Anteater, Armadillo, and Oryc- 

 terope, and is easily separable from the biceps, which does not 

 seem to be the case in the Orycterope (Trans. Linn. Soc. 

 p. 589). 



Gluteus medius and minimus were inseparably united, a 

 condition which is described by Meckel : a similar fusion takes 

 place in Clioloipus^ Dasypus^ and Myrmecophaga juhata and 

 didactyla ; E.app, however, found them distinct in M. taman- 

 dua. Their attachments are as usual. 



Tensor vaginae femoris arises from the anterior fifth of the 

 crest of the ilium, fleshy and tendinous, passes downwards 

 into a line, about half an inch long, on the outer side of the 

 femur below the great trochanter : this is the muscle to which 

 Cuvier gives the name gluteus minimus ; but its origin is on 

 a plane superficial to the gluteus medius muscle, and anterior 

 to the gluteus maximus. This muscle in the Armadillo is 

 larger and more expanded ; in that animal its insertion is not 

 exactly into the bone, but into a tendinous sling passing from 

 the third trochanter to the external condyloid ridge on the 

 femur. 



Pyriformis, quite distinct from the loAver border of the glu- 

 teus medius, arises from the margin of the sacrum, and not 

 from its anterior aspect, agreeing in this respect with Dasypus ; 

 it is inserted as usual. It has no fibres from the ilium, trom 

 which bone it takes its attachment in Orycteropus. It is not 

 divided into segments. 



Obturator internus, very small and displaced on account of 

 the position of the lesser sciatic notch. Siisemuhl denies the 

 existence of this muscle ; and truly there is no muscle within 

 the pelvis occupying the ordinary site of the inner obturator ; 

 but Meckel observes properly that the obturator internus lies 

 beneath the obturator externus. This muscle is absent in Da- 

 sypus and in the Tamandua. The gemelli are both present, and 

 about equal in size in the Ai, as also, according to Rapp, in 

 the Tamandua and also in Dasypus. Both obturators and 

 gemelli, however, exist in Orycteropus. 



Quadi'atus femoris is present, but small. It seems to be 

 absent in the Orycterope and the Anteaters ; it is present, 

 however, in the Armadillo. Meckel describes it as Vv^ell de- 

 veloped in this animal. Obturator externus is normal as in all 

 the Edentates. 



Psoadiliacus is large and remarkable, unsegmented at it8 

 origin, which is as usual ; its insertion is into the lesser tro- 

 chanter and a ridge prolonged down the thigh for an inch be- 



