MUSCLES OF THE HIND LIMB. Pret 
passes into a tendinous insertion on the ectal side of the dorsal margin of the 
patella. 
The crureus (Plate 6, fig. 1, 7) arises along the anterior margin of the femur 
and is almost inseparably united to the vastus externus. It inserts medially on 
the patella beneath the insertions of the vastus externus and the rectus femoris. 
The vastus internus (Plate 4, fig. 2, b) is distinct, instead of being fused with 
the crureus as in Gymnura. Its origin is from the antero-ental side of the 
proximal third of the femur, and its insertion is at the ento-dorsal corner of the 
patella. 
The pectineus (Plate 4, fig. 2, n) is a thick muscle somewhat triangular in 
section. Its origin is just dorsal to that of the adductor longus for about 9 mm. 
on the anterior rim of the pelvis and posteriorly nearly to the acetabulum. It 
is visible superficially for but a slight space, and passes beneath the surrounding 
muscles to its insertion as a somewhat tendinous sheet on the inner posterior 
length of the femur from the lesser trochanter nearly to the distal head. It is 
thus slightly more developed than in Gymnura. 
The quadratus femoris (Plate 4, fig. 2, h) is large, from an origin 19 mm. long 
on the posterior edge of the ischial tuberosity, covered by the adductor magnus 
and the semitendinous. It is inserted by a tendon on the lesser trochanter and 
the intertrochanteric fossa. Its relations are closely similar to those in Potamo- 
gale and Centetes. No connection with adductor brevis was found such as is 
described for Gymnura. 
The obturator externus arises from the membrane covering the obturator 
foramen and from the bone bordering it. The insertion is by tendon into the 
trochanteric fossa posterior and ental to the great trochanter. This muscle is 
essentially similar to that of Gymnura, Centetes, Potamogale. 
As pointed out by Dobson, Solenodon differs from Centetes and agrees with 
Gymnura, Potamogale, Erinaceus, and Myogale in the absence of an obturator 
internus. 
The gracilis (Plate 4, fig. 2, g) is large and arises from the dorsal half of the 
posterior margin of the ischium. It is somewhat pyramidal at first, becoming a 
flat muscular sheet just below the head of the tibia along its antero-internal 
border. As noted by Dobson, the gracilis muscles of the two sides of the body 
are well separated in Solenodon and related genera, but united medially in Cen- 
tetes. No accessorius portion of this muscle was observed. 
The biceps femoris (Plate 6, fig. 1, 7) is from two heads. Of these, the larger 
is from the ischial tuberosity, while the smaller consists of a flat tendinous mem- 
