188 SPECIAL ANATOMY. 



b. Drawn upwards, towards the os hyoides (Epiglottis curved 

 backwards), by: hyo-thyreoid. 



c. The epiglottis bent back (and the entrance shut) by : reflect- 

 or epiglottidis. 



d. The vocal cords removed from one another, and the entrance 

 widened by : crico-aryisenoideus posticus. 



II. Trunk. 



409. A. The neck is : 



a. Flexed by : longus colli and scaleni (3) of both sides. 



b. Extended by: splenius colli, transversal, (and spinales, 

 semi-, inter-spinal es, multifidi). 



c. Drawn sideways by : transversal., cervical, descend., spinalis 

 and semispinalis cervicis, obliq. capit. infer, (on the atlas), in- 

 tertransv. and multifid., scalenus med. and post, of one side. 

 Rotated by: splen. colli., transversal., cervicalis of the other. 

 The skin of the neck is moved by: platysmamyoides. 



410. B. Thorax. 1. The thoracic portion of the vertebral 

 column is: 



a. Flexed by : recti, obliq. and pyramidales abdominis. 



b. Extended by : multifidi, inter spinales, spinales and semi- 

 spinal, dorsi, sacro-lumbales and longissim. dorsi. 



c. Drawn sideways by : multifidus on one side ; rotated by : 

 rotatores dorsi and multijidus of one side. 



411. 2. The ribs are : 



a. Elevated and the chest widened as the lungs expand, and 

 the diaphragm contracts downwards (descends) by: inter co stales, 

 levatores costarum, scaleni (they fix the first ribs), serratus pos- 

 ticus superior. As in inspiration. 



NOTE. Deep inspiration is effected by sterno-ckidomast., subclavius, pcdorales, 

 serratus anticus, latissim. dorsi, cervicalis descend. The intcrcostales (and infra- 

 costales) approximate the ribs, since they draw them upwards (inspiration) or 

 downwards (expiration). 



b. Drawn downwards by : intercostales, serratus post, inferior, 

 triangularis sterni, quadratus lumborum (fixes the twelfth rib), 

 abdominal muscles. As in expiration. 



412. 3. The sternum is : 



a. Drawn up by: sterno-cleido-mast., sterno-hyoidd. 



b. Downwards by : recti abdominis. 



413. C. The lumbar portion of the vertebral column is: 



a. Flexed by: psoas major et minor of both sides. 



b. Extended by : longissim. dorsi, ileolumbalis. 



