The anatomy of the hypophysis of whales

Abstract

The Vmiversity of Chicago FOUR TEXT FIQUILE~ AND THREE P L A~S (THIRTEEN FIG^)In 1929 Wislocki published a description of the hypophysis of the porpoise (Tursiops truncatus). The two principal conclusions of this study were that in the porpoise the processus infundibuli is separated anatomically from the buccal portion of the hypophysis and that the pars intermedia and hypophyseal cleft are completely lacking in the adult porpoise, the pars buccalis consisting solely of a pars tuberalis and of a pars distalis.These findings interested Geiling so much that he undertook an investigation of the hypophysis of the larger whales with the object of studying the active principles of the two dissociated components if the parts of their pituitaries proved to be anatomically separate as in the porpoise. A brief note, meanwhile, by ValsS ('34) on the hormone content of the hypophysis of the blue whale (Balaenoptera sibbaldii) stated that the anterior and posterior lobes of the pituitary of this whale are easily separable. The first fruits of Geiling's study ( '35) appeared in a rather extensive report on the assay of the pituitary glands of finback and sperm whales. The anatomical observations accompanying these studies bore out the great resemblance of the finback and sperm whales' hypophyses to that of the porpoise ('29). According to Geiling's observations, the pituitary glands in these whales are made up of a large, flattened anterior lobe and a smaller posterior lobe separated by a septum. Moreover, there is no 17

The Cetacean Central Nervous System

“…The gross morphology of the hypophysis is similar in Odontoceti and Mysticeti (Wislocki, 1929;Geiling, Tarr & Tarr, 1935;Wislocki & Geiling, 1936;Valso, 1936;Hanstrom, 1944). From measurements given by some of these authors it is evident that the gland varies considerably in size with species, and in the larger whales the amount of tissue per unit of body weight is very small compared with other mammals.…”

The Physiology and Pharmacology of the Pituitary Body.

“…The hyaline bodies of Herring, which can be found in the pars neuralis of the whale (Wislocki and Geiling, 1936), are therefore not derived from juxtaposed cells of the pars buccalis (pars intermedia) as has been suggested from studies of the pituitary of other mammals. In fact, Gersh and Tarr [II] (1935) offer good evidence that such hyaHne bodies are fixation artefacts and are unrelated to the amount of pressor hormone in the pars neuraHs.…”

Pathophysiology and clinical features of pituitary pars intermedia dysfunction

“…Development of the PI varies greatly among different animals. The horse has a well‐developed PI; dogs, cats, cattle and sheep have a moderate sized lobe while whales and birds lack a PI altogether (Wislocki and Geiling ; Rahn and Painter ). Although the PI is relatively distinct in the human fetus, the adult human lacks a well‐defined intermediate lobe, instead melanotropes are found dispersed throughout the pars distalis (Saland ).…”