354 



ZOOLOGY FOR MEDICAL STUDENTS 



CHAP. 



Fig. 148. 



A, Horizontal section through gill-clefts of Haddock : B, a single branchial arch from A shown 

 on a larger scale, a, Afferent vessel ; b.a, branchial arch ; e, efferent vessel ; ^.r, gill-rakers ; 

 M, mouth opening with teeth ; oes, oesophagus ; op, operculum (that of the left side has been pulled 

 outwards to display the gills more clearly) ; p.t, pharyngeal teeth ; r.i, respiratory lamellae ; 

 v.c. II-VI, visceral clefts. 



