64 MESSRS. MURIE AND MIVART ON THE 
the gluteus medius. It arises from the inferior (anterior) surface of the sacrum, 
reaching as high up as the middle of the auricular surface. Converging as usual, it is 
inserted into almost the very summit of the posterior border of the peroneal trochanter, 
beneath the insertion of the gluteus medius. 
This muscle is connected with the gluteus medius by tendon as well as by muscular 
fibre, both in L. varius and L. nigrifrons. In L. wanthomystaw it is also partly adherent 
to the gluteus medius, but still more distinct than in those two species. 
Galago agrees with Lemur, excepting that the muscle reaches no higher than the 
lower part of the sacro-iliac synchondrosis (PI. V. fig. 19, and Pl. VI. fig. 25, Py). 
In Tursius, as before said, Burmeister’ has described as pyriformis a part of the 
gluteus maximus He says, indeed, that a double pyriformis exists in this genus. 
His first pyriformis (tab. 4. fig. 5. no. 7) is part of our gluteus maximus; his second part 
is described as a triangular muscle springing from the sacrum and going to the thigh; 
this portion appears to be the pyriformis proper. We are inclined to doubt the accu- 
racy of the delineation of this muscle. 
It is described by Professor Owen in Cheiromys, p. 145. 
GEMELLUS SUPERIOR.—This springs from the spine of the ischium, and is inserted into 
the anterior (upper) part of the deep surface of the tendon of the obturator internus, 
and, in common with it, into the trochanter fossa. 
The gemelli are figured by Cuvier in L. varius, pl. 70. fig. 2, e and e’. 
The other genera present similar characters. Illustrated in Galago crassicaudatus, 
Pl. VI. fig. 25, G.s, and in Tarsius, 1. c. p. 70. tab. in fig. 6. no. 8, d, 
GEMELLUS INFERIOR’.—This, which is larger than the preceding, arises from the upper 
(posterior) surface of the tuberosity of the ischium and from the lower part of the so- 
called “ascending” ramus of the ischium. It is inserted into the posterior (inferior) 
surface of the tendon of the obturator internus and also into the adjacent part of the 
tendon of the obturator externus, and also between them both into the trochanteric 
fossa. The two gemelli muscles are closely connected together, especially at their 
origin. 
That of Galago crassicaudatus is shown in Pl. V. fig. 21, and Pl. VI. fig. 25, G7. 
When describing the pectineus, Owen* mentions that “beneath it are strong and 
thick gemelli converging from their origin on the anterior surface of the pubis and 
ischium to the interspace between the small and large trochanter.” 
OBTURATOR EXTERNUS*—A very thick layer with origin from the whole external 
circumference of the obturator foramen and from the lower half of the obturator mem- 
brane. It is inserted, by a very strong tendon, into the lowest portion of the fossa 
behind the peroneal trochanter. 
1 Loe. cit. p. 69, tab. 4. fig. 5. no. 7, a. 
? Tarsius, loc. cit. pl. 70. tab. 4. fig. 6. no. 8, a, > Loc, cit: p. 66, 
* Tarsius, loc. cit, p, 71, tab. 4. fig. 6. no. 10, 
