Bull. U. S. B. F. 191 2. 



Plate LXI. 



GILI- FILASIENTS OF 4TII ARCH 



HEAD OF KIDNEY 



ESOPHAGUS 



OPHRCfLCM 



PREOPERCfLl'M 



CHEEK MUSCI.E IN SECTION 



DENTARY 



ORAL MEMBRANE _ 



BRANCHIAL AKCH 



3KI. BRANCHIAL ARCH 



D BRANCHIAL ARCH 



HRANCIIIAL ARCH 



HYOID CORN!' 



Fig. 15. — Composite picture of lateral and longritudinal distribution of nonnal thyroid in the Salnionidie. with vessels. 



1ST COPILA (CARTILAGE) 

 1ST BASIBR.\NCHIAL 

 ; 2ND BASIBRANCHUL 



: MUSCLE 

 ORAL MEMBRANE ; 



TEETH OF TONGUE ill i 



f JXD COPULA (CARTILAGE) 



4TH BASIBR.AXCHIAL 

 3RD BASIBRANCHIAL 

 --.,i 3RD COPULA (CARTILAGE) 



■-.-l. i" ••;— . VENOUS SINUS 



basihyal ; • ; 



; tongue cartilage 

 hVpohy.ai, 



■• ESOPHAGEAL MUCOSA 



ANDiARhllLAR TISSUE 



BULBUS AORTAE 



.VENTRICLE 



SVMPHS'SIS OF DENTARV 



: Jl GULAR PIT 

 BRANCHIAL SEPTUM 



HYPOHVAL SYMPHYSIS 

 M USCLE 



TiPITHELIUM 



SUBMUCOSA 

 SYMPHYSIS OF CLAVICLE— CORACOID PAIRS 

 ; VENTRAL AORTA 



UROHVAL 



BRANCHIAL SPACE 



Fig. 16. — Longitudinal and dorso-ventral distribution of thyroid in tlu- s.-iltnonida'. 



