126 



HITCHCOCK'S ANATOMY 



Fig, 141. 



which completely cover the 

 space below the border of the 

 ribs, and above the innomina- 

 tum. They are arranged un- 

 der four different names, since 

 they run in different direc- 

 tions as they encircle the ab- 

 domen. By their contraction 

 they press upon the digestive 

 organs, and thus diminish the 

 cavity of the abdomen, and, 

 in proportion to the elasticity 

 of the diaphragm, the thorax 

 also. Hence these are the 

 essential instruments in cough- 

 ing, laughing, crying, and 

 sneezing, as well as in sing- 

 ing, shouting, or any action 

 requiring expulsive effort. By 

 their elasticity they also per- 

 form the function of expira- 

 tion in natural breathing, as 

 well as keep up a tonic pres- 

 sure upon the stomach and 

 alimentary canal. 



252. Great Psoas Muscle. 

 — The Great Psoas Muscle, 

 known in animals as the ten- 

 der loin (from the Greek 

 signifying a loin), is the 

 one which bends the thigh upon, or towards the trunk. 

 It has its origin from the last dorsal and four upper lum- 

 bar vertebra, and passes from thence downwards and for- 

 wards, gliding over the edge of the innominatum, and attaches 



A Lateral View of the Muscles of the 

 Trunk, especially on the Abdomen. 1, 

 Latissimus Dorsi. 2, Serratus Major An- 

 ticus. 3, Upper portion of the External 

 Oblique. 4, Two of the External Inter- 

 costal Muscles. 5, Two of the Internal 

 Intercostal Muscles. 6, Transversalis Ab- 

 dominis. 7, Fascia Lumborum. 8, Poste- 

 rior part of the Sheath of the Rectus, or 

 Anterior Aponeurosis of the Transversalis 

 Muscle. 9, The Eectus Abdominis cut off 

 and in its Sheath. 10, Eectus Abdominis 

 of the Eight Side. 11, Crural Arch. 12, 

 Cluteus Magnus — Medius and Tensor Va- 

 ginae Femoris covered by the Fascia Lata. 



Under how many heads are they arranged ? What actions do they accomplish when 

 contracted? 252. What is the scientific name of the "tender loin?" Give its attach- 

 ments. 



