PLATES 



EXPLANATION OF FIGURES 



Figures 9-11, 13-19, 21 and 22 were drawn by Miss Herford in tlie Department 

 of Comparative Anatomy of the Harvard Medical School, from models by the 

 author. Theremainingfigures were drawn by Miss Whitman, Cornell University. 



ABBREVIATIONS 



A. A.I II, third aortic arch 



A.A.IV, fourth aortic arch 



A.C., carotid artery 



cm, complex III 



CIV, complex IV 



C.P., pericardial cavity 



D.br.II, ductus branchialis II 



D.br.IV, ductus branchialis IV 



D.ph-br. Ill, ductus pharyngeo-bran- 



chialis III 

 D.ph-br. IV, ductus pharyngeo-bran- 



chialis IV 

 D.C, ductus cervicalis 

 D.thyr., ductus thyreoglossus 

 D.v.II, diverticulum ventrale II 

 D.v.III, diverticulum ventrale III 

 D.v.IV, diverticulum ventrale IV 

 E, esophagus 



Epi.II, epibranchial placode II 

 Epi.III, epibranchial placode III 

 Epi.IV, epibranchial placode IV 

 F.br.I, fissura branchialis I (cleft I) 

 F.br.II, fissur^ branchialis II (cleft II) 

 F.br.III, fissura branchialis III (cleft 



III) 

 F.br.IV, fissura branchialis IV 



G.IX, ganglion petrosum (IX) 



G.X, ganglion nodosum (X) 



N.IX, nervus glossopharyngeus (IX) 



N.X, nervus vagus (X) 



N.XII, nervus hypoglossus (XII) 



N.symp., nervus sympatheticus 



P. Ill, parathyreoid III 



P. IV, parathyreoid IV 



Ph., pharynx 



S.br.I, sacculus branchialis I (pouch I) 



S.br.II, sacculus branchialis II (pouch 



11) 

 S.br.III, sacculus branchialis III 



(pouch III) 

 S.br.IV, sacculus branchialis IV (pouch 



IV) 

 S.C, sinus cervicalis 

 T.A., truncus aorticus 

 Th., thymus 

 Thyr., thyreoid 

 Tr., trachea 



U , corpus ultimobranchiale 

 V.br.II, vesicula branchialis II 

 V.C, vesicula cervicalis 

 V.J ., vena jugularis 



387 



