MUSCLES OF THE HIND LIMB. 27 



passes into a tendinous insertion on tlie ectal side of tlic dorsal margin of tlie 

 patella. 



The cnireus (Plate 6, iig. 1, /) 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, 6) is distinct, instead of being fused with 

 the crureus as in Gymnura. Its origin is from the antcro-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, /;) 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 ohhirator externus arises from the memjjrane covering the obturator 

 foramen and from the bone bortlering 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 mecUally in Cen- 

 tetes. No accessorius portion of this muscle was observed. 



The biceps femoris (Plate 6, fig. 1, i) is from two heads. Of these, the larger 

 is from the ischial tuberosity, while the smaller consists of a flat tendinous mem- 



