172 MUSCLE TISSUE 



extensor coimiiunis, though here they are not so much 

 needed, and their function is not so evident. 



Extensors of the foot slightly rotate inward ; flexors of 

 the foot slightly rotate outward; plantaris indirectly 

 pulls up the capsule of the ankle-joint and slightly aids 

 the gastrocnemius. 



Flexors of the foot. Extensors of the foot. 



Tibialis anticus. Tendo Achillis. 



Extensor communis digitorum. Peroneus longus and brevis. 

 Extensor proprius hallucis. Tibialis posticus. 



Peroneus tertius. Flexor longus digitorum and 



hallucis. 



Adduction. Abduction. 



Tibialis posticus (strongly). Peroneus brevis. 



Tendo Achillis (weakly) . Peroneus longus. 



Perhaps tendons behind the 



inner malleolus, perhaps 



the tibialis anticus. 



Rotation in. Rotation out. 



Tibialis anticus (strongly). Peroneus longus. 



Tendo Achillis. Extensor communis digitorum. 



Peroneus tertius. 



The Interosseous Muscles. Interossei, as in the hand, 

 are seven in number, four dorsal and three plantar. 

 The dorsal project downward as low as the plantar, 

 and alternate with them. Only one muscle in the 

 first space, two in the others. The second phalanges 

 are their centre of insertion. 



QUESTIONS 



1. Name the three varieties of muscle tissue. 



2. What does the sarcoplasm represent in muscle tissue? 



3. Does the sarcoplasm possess the quality of contractility? 



4. What do you understand by a skeletal muscle? 



5 What forms the fibers in a muscle? The primary bundles? 

 Secondary? 



6. What is the function of the epimysium? Perimysium? Endo- 

 mysium? 



7. Where are voluntary striated muscles found in the body? 

 Involuntary non-striated? 



