(C 1
6
Fig. 25. Diagrammatic midsagittal sections to illustrate the main features of pituitary structure in the different fish groups. In all cases, anterior is to the left. ( A )
myxinoid, ( B ) lamprey, ( C ) Acipenser, ( D ) Amia, ( E ) Polypterus, ( F ) teleost,
( G ) elasmobranch, and ( H ) dipnoan. Small dots, nervous tissue; large solid dots,
stainable neurosecretory material; large open dots, pars distalis; horizontal lines, pars
intermedia; thick black lines, blood vessels which appear to convey neurosecretory
products to the adenohypophysis or ( myxinoid) to the neurohypophysis; oblique
hatching, connective tissue; a, hypophysial cavity; b, hypophysial duct; c, ventral
lobe of elasmobranchs; and 111, third ventricle.
75
6
Fig. 25. Diagrammatic midsagittal sections to illustrate the main features of pituitary structure in the different fish groups. In all cases, anterior is to the left. ( A )
myxinoid, ( B ) lamprey, ( C ) Acipenser, ( D ) Amia, ( E ) Polypterus, ( F ) teleost,
( G ) elasmobranch, and ( H ) dipnoan. Small dots, nervous tissue; large solid dots,
stainable neurosecretory material; large open dots, pars distalis; horizontal lines, pars
intermedia; thick black lines, blood vessels which appear to convey neurosecretory
products to the adenohypophysis or ( myxinoid) to the neurohypophysis; oblique
hatching, connective tissue; a, hypophysial cavity; b, hypophysial duct; c, ventral
lobe of elasmobranchs; and 111, third ventricle.
75