iio6 



A MANUAL OF ANATOMY 



Great Cornu of Hyoid Bone _ 



Small Cornu of Hyoid Bone._ 

 Body of Hyoid Bone.. 



Thyro-hyoid Membrane -- 

 Levator Glandulae \ 

 Thyroidae Muscle / " 

 Thyroid Cartilage - - 



Crico-thyroid Membrane __ 

 Pyramid - - 

 Cricoid Cartilage 

 Lateral Lobe of Thyroid Body 

 Isthmus 



Trachea 



chin and above the body of the hyoid bone, one being on either side 

 of the median Hne. Each gland receives its afferent vessels from 

 (i) the mesial portions of the lower lip and lower gum; (2) the tip 

 of the tongue and adjacent portion of the floor of the mouth; and 

 (3) the integument of the chin. Their efferent vessels pass to (i) the 

 submaxillary lymphatic glands, and (2) that gland of the internal 

 group of the substerno-mastoid glands which lies on a level with 

 ,, . . . the cricoid cartilage of the 



Ep.glott.s j^y^^ 



Infrahyoid Region. — The re- 

 gion from the hyoid bone down- 

 wards to the interclavicular 

 notch on the upper border of 

 the manubrium sterni is of con- 

 siderable importance in connec- 

 tion with bronchocele or goitre, 

 laryngotomy, and tracheotomy. 

 The body of the hyoid bone is 

 a well-marked structure, along 

 with the great cornu on either 

 side of it. Below the hyoid 

 bone there is the thyro-hyoid 

 membrane, which passes up- 

 wards within the lower border 

 of the hyoid bone. The next 

 structure is the thyroid carti- 

 lage, the upper border of which 

 presents a well-marked median 

 notch, whilst its two 

 alse form by their union 

 the prominent isthmus, 

 or pomum Adami. 



Succeeding to the 

 thyroid cartilage there 

 is a narrow interval, 

 which is occupied by 

 the crico-thyroid mem- 

 brane, and immediately 

 below this membrane is the narrow anterior part of the cricoid 

 cartilage. The crico-thyroid membrane is only exposed close to 

 the median line, being elsewhere covered by the two crico-thyroid 

 muscles. The exposed part of the membrane is crossed by the 

 crico-thyroid arterial arch, which is situated midway between the 

 thyroid and cricoid cartilages, and lying upon the membrane there 

 may be one or two prelaryngeal lymphatic glands. Laryngotomy 

 may be performed in the crico-thyroid region, and the crico-thyroid 

 arterial arch has to be borne in mind. 



Succeeding to the cricoid cartilage is the trachea, which, as it 

 descends, inclines backwards, and therefore becomes somewhat 



Right Bronchus 

 Eparterial Bronchus, 

 Hyparterial Bronchus.^ 



Left Bronchus 



Fig. 50. — The Hyoid BiONE, Larynx, 

 Trachea, Bronchi, and Thyroid Body 

 (Anterior View). 



