24'2 MR. G. E. DOBSON ON CAPROMYS MELANTJRUS. [Apr. 1, 



Interossei dorsales. — These muscles are fused with the palmar 

 interossei (jtexores breves) throughout their muscular extent. Of 

 the pair of flexores breves for each of the three middle digits, each 

 muscle sends a long tendon forwards and dorsalwards alongside 

 each digit to unite with the tendon of its fellow passing along the 

 other side of that digit over the base of the second phalanx of the 

 same digit into which it is inserted, crossed by the tendon of the 

 long extensor going to the terminal phalanx. Thus each of the 

 three middle digits of the manus has a pair of dorsal as well as of 

 palmar interossei tendons. The fifth digit, however, has but a 

 single interosseous tendon, and the small pollex appears to have none. 



Muscles of the Hind Limbs. 



Gluteus maximus is wide but thin, arising from the anterior 

 extremity of the ilium and from the spinous processes of the 

 sacral and coccygeal vertebrae, and is inserted into the fascia lata 

 of the thigh and into the lower external third of the shaft of the 

 femur. 



Gluteus medius is of great size. It arises from the spines of the 

 sacral and coccygeal vertebrae under cover of the gluteus maximus 

 and from the greater part of the upper surface of the ilium, including 

 within the fold thus formed the small gluteus minimus ; the fibres 

 are inserted by two short and thick tendons into the upper and 

 lower sides of the greater trochanter. 



Gluteus minimus (included as above described) is a narrow long 

 muscle arising from the upper and inner part of the anterior half of 

 the ilium, and from the sacrum, along with the gl. medius, forms a 

 flat tendon inserted into the greater trochanter between the two 

 tendons of the gl. medius. 



Piriformis aud obturator internus are both absent. 



Quadra tus femoris arises under cover of the adductor magnus 

 from the tuber ischii, and is inserted into the outer side of the lesser 

 trochanter. 



Gemelli appear to be united, forming a broad flat muscle arising 

 from the whole length of the ischium from the acetabulum to the 

 tuber ischii and inserted into the greater trochanter under cover of 

 and below the gl. medius. 



Biceps flexor ci'uris arises by two heads, a superficial and a deep : 

 the former from the transverse processes of the last two coccygeal 

 vertebrae ; its fibres pass outwards under cover of the ilio-caudal 

 muscles, overlying the great sciatic nerve, and are inserted into the 

 head of the fibula and into the fascia covering the knee-joint ; the 

 deep head arises from the tuber ischii in connexion with the adductor 

 magnus by a narrow tendon, and, spreading out into a fan-shaped 

 muscle, is inserted above in connexion with the tendinous aponeurosis 

 of the superficial part into the head of the fibula, and, lower down, 

 into the fascia covering the peroneal muscles and into the tendo- 

 achillis. 



The sartor ius is not represented. 



