Abstract

LONDON Royal Society, January 31. R. T. HILL and A. S. PARKES: Hypophysectomy of birds. (6) Plumage changes in hypophysectomised fowls. Hypophysectomy of the Brown Leghorn cock results in the loss of most or all of the black pigment from the feathers of the under-neck, breast and legs. The later growing feathers, particularly, are usually devoid of black and may be extensively fringed. The new plumage over the rest of the body is characterised by loss of black pigment and increase of fringing due to lack of barbules. These changes are so similar to those which follow thyroidectomy that they may reasonably be supposed to be due to thyroid deficiency, which is well known to follow hypophy-sectomy in mammals. (5) Effect of replacement therapy on the gonads, accessory organs and secondary sexual characters of hypophysectomised fowls. Fowls injected with ox anterior lobe extract for 4–6 days after hypophysectomy all showed a temporary increase in the size of the comb and, in the male, the atrophy of the testes was slightly retarded. Prolonged injection after operation, however, failed to avert (a) the comb shrinkage, (b) the testes atrophy, or (c) the plumage changes, which follow hypophysectomy. Attempts to restore the atrophied gonads and combs of hypophysectomised birds by injections of anterior lobe and urine of pregnancy extracts were comparatively unsuccessful. H. MUIR EVANS: The brain of Gadus with special reference to the medulla oblongata and its variations according to the feeding habits of different Gadidae (1 and 2). The divergence of opinion of the significance of the various lobes in Gadus has necessitated a detailed microscopic examination of serial sections of the medulla of the whiting; the result of which is to confirm the views of Goronowitsch and others, and to dispute the conclusions of C. J. Herrick. The facial lobes described by the former writers are held to be true facial lobes, comparable to the single facial lobe of the roach, as a type of cyprinoid brain, which is the result of the fusion of two facial elements. Different species of gadoids can be classified according to their diet, and both diet and dentition are reflected in the pattern of the medulla oblongata. At one extreme is the haddock, feeding on Crustacea and mollusca, with a large facial lobe and a small somatic sensory lobe, and at the other end species like the ling and the pollack, feeding almost entirely on fish, with a small facial lobe and a very large somatic sensory lobe. In between there is a gradual transition both in types of medulla and in feeding habits, as we pass from the haddock to the cod, whiting, ling, pollack and hake. H. W. FLOREY and H. E. HARDING: A humoral control of the secretion of Brunner's glands. The secretion of Brunner's glands of the cat occurs independently of extrinsic innervation. The glands are activated after the taking of food by a blood-borne stimulus—a hormone or secretagogue.

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