166 MYOLOGY, OR ANATOMY OF MUSCULAR SYSTEM 



shut off the posterior nares, and the food is guided into the 

 lower pharynx, where it is grasped by the constrictors in suc- 

 cession and forced into the esophagus. 



H. THE DEEP NECK MUSCLES 



These are divided by the transverse process into two groups. 

 The outer from the processes to the ribs corresponding to the 

 intercostals, those from the processes to the shoulder blade 

 corresponding to the serratus magnus; the inner group passes 

 from one process to another, long or short. 



OUTER GROUP (four in number). 1. M. Scalenus Anticus. 

 Origin, anterior tubercle of the transverse process of the third, 

 fourth, fifth, and sixth cervical vertebrae; insertion, by a thick 

 flat tendon into the scalene tubercle of the first rib; the pleura 

 is attached to the lower part of the inner surface of this muscle. 



2. M. Scalenus Medius. Origin, tendinous above, muscular 

 below, from posterior tubercle of transverse process of all 

 the cervical vertebrae (sometimes not of the atlas); insertion, 

 upper edge and outer surface of the first rib from the tuberosity 

 to the subclavian groove. 



3. M. Scalenus Posticus (smaller than the others). Origin, by 

 two or three tendons from the posterior tubercles of the lower 

 two or three cervical vertebrae; insertion, by an aponeurotic 

 tendon into the second rib external to the serratus posticus 

 superior. 



Some regard the scalenus mass as one muscle with three 

 insertions. 



4. M. Lcvator Scapulae (leva tor anguli scapulae). Origin, 

 by distinct slips from the transverse process of the upper 

 four cervical vertebrae between the attachments of the splenius 

 and scaleni; insertion, posterior border of the scapula from the 

 spine to the superior angle. 



Vertebral attachments various; a slip to it from the occipital 

 bone or mastoid process; parts from the vertebrae may remain 

 separate to their insertion. In quadrupeds it unites with the 

 serratus anticus (magnus), and forms one muscle; may send 

 a slip to the scaleni, trapezius, serrated muscles, or first and 

 second ribs. 



INNER GROUP. Long Muscles. 1. M. longus colli rests on 

 the front of the vertebral column from the atlas to the third 



