2G8 COMPARATIVE MYOLOGY. 



tlie auterior one has no ischial origin. The sartorim has an oiigin from the 

 venter of the ilium, and its fleshy portion reaches the tibia. The gracilis is 

 very small and thin. 



In the anterior tibial region we find the following muscles : — The tibiaUs 

 uniicus, corresponding to the fleshy portion of the flexor metatarsi, partly 

 covers the extensor communis ; it arises from tTie tibial crest and tuberosity, 

 receives a slip from the peroneus, and is inserted by a tendon to the meta- 

 tarsal element of the hallux. If the hallux is complete, a tendinous slip 

 passes to the distal phalanx. The tendon of this muscle is bound down by a 

 fibrous band, from which a strong slip passes under the tendon, becoming 

 attached to the tibia, and to the metatarsal bone of the middle digit, to some 

 extent corresponding to the fibrous portion of the flexor metatarsi. The 

 eztciscr communis digitorum arises bv a strong tendon from between the 

 femoral condyle and the trochlea ; its tendon of insertion passes over the tarsus 

 much in the usual manner, divides into four slips, and is inserted as in the 

 anterior limb. The peroneus longus is placed between the preceding muscle 

 and the peroneus brevis ; it arises fropi the superior part of the tibia, and 

 its tendon, reaching the tarsus, divides, a slip passing inwards to the first meta- 

 tarsal bone, the rest winding round the cuboid to gaiii the back of the joint, 

 and become attached to the metatarsal bone of the hallux. This muscle seems 

 to be an abductor of the extremity. The peroneus brevis consists of two parts 

 — a superior, arising from the upper third of the fibula, and having a long thin 

 tendon, which passes underneath the peroneus longus, descends and joins the 

 extensor tendon of the external digit. The inferior part is penniform, and 

 arises also from the fibula, ending in a strong tendon which is inserted to the 

 external metatarsal bone. The superior portion is the extensor proprius of the 

 outer digit, the inferior an abductor of the extremity. 



In the posterior tibial region we find the plantaris wanting. The flexor 

 perforatum is somewhat blended with the gai<trocnemiu8, and its tendon 

 is divided into four parts, and inserted as in the anterior extremity. 

 The perforans tendon divides into four, and if the hallux is perfect into five 

 slips, proceeding to the distal phalanges. Between the perforans and flexor 

 accessorius is a separate muscle, the tibialis posticus^ very tliin and slender, 

 arising from the fibula and tibia above, its tendon accompanying that of the 

 accessorius into its sheath, and afterwards becoming blended with the posterior 

 tai'sal ligament. 



We note the following muscles in the metatarsal region. The extensor pedis 

 brevis consists usually of three bundles, and it joins the extensor tendons of tho 

 three outer digits. The perforans has a small accessory muscle, which arises on 

 the outside of the tarsus. The lumbricales and interossei resemble their ana- 

 logues of the metacarpus. The muscles proper to the hallux are either absent, 

 or too rudimentary to merit notice. An abductor minimi digiti is present, 

 and corresponds to that of the metacarpus. 



RODENTIA. 



The most prominent feature in the myology of the rabbit is the enormous 

 development of the dorso-lumbar, sublumbar, gluteal, and femoral muscles. 



