THE NASAL FOSSAE. 135 



The turbinals on the lateral wall of each fossa are .usually described as three in 

 number, viz., two on the lateral mass of the ethmoid, which are known as the 

 superior and middle turbinals (superior and inferior ethmoidal conchse), and one, 

 the inferior turbinal, on the superior maxillary bone (maxillary concha). Each 

 concha overhangs and partially separates from the general cavity of the fossa a 

 groove-like space, which is known as the corresponding meatus (superior, middle, or 



9 ~ 



Fig. 154. VIEW OF THE RIGHT NASAL FOSSA AS SEEN IN A SECTION THROUGH THE SKULL, TAKEN JUST 



TO THE RIGHT OF THE SEPTUM. (E. A. S.) 



1, incisor canal ; 2, bone of hard palate ; 8 and 4, parts of the mesial crus of the cartilage of the 

 aperture ; 5, anterior part of the same cartilage ; 6, cartilage of the septum ; 7, groove leading to 

 middle meatus ; 8, agger nasi ; 9, frontal sinus ; 10, inferior ethmoidal concha ; 11, superior ethmoidal 

 concha; 12, recess of upper meatus above superior concha; ]3, entrance to sphenoidal sinus; 14, 

 pituitary fossa ; 15, sphenoidal sinus ; 16, inferior turbinal (maxillary concha) ; 17, rod passed into 

 Eustachian tube ; 18, salpingo-pharyngeal fold : immediately behind this is the lateral recess of the 

 pharynx, not specially indicated in the drawing ; 19, soft palate ; 20, uvula ; 21, tongue. 



inferior, as the case may be). The groove of the superior meatus between the 

 superior and middle conchse is also termed the ethmoidal fissure. This meatus is 

 relatively small, corresponding with the small size and extent of its overhanging 

 concha : into it the posterior ethmoidal cells open by one or two apertures (fig. 155). 

 The middle turbinal or concha is large, and overhangs a correspondingly large 

 middle meatus, which'can only be properly seen on cutting away the concha (fig. 155). 

 It is .then found that the meatus extends under the anterior part of the turbinal 

 into a gradually narrowing funnel-shaped diverticulum (wfundilulum) which leads 



