. The pigmentary, growth and endocrine disturbances induced in the aunran tadpole by the early ablation of the pars buccalis of the hypophysis. erior lobeneither alters the nature of this curve nor produces quantitativeresults of unquestionable significance, although there appearsto result in most cases from this diet a small increment in sizeand a somewhat earlier completion of metamorphosis. The growth curve of albinous frog larvae with a liver-lettucediet differs in character and in magnitude from that of the nor-mals (fig. 1). I have described these changes previously (Smith,18), and later
. The pigmentary, growth and endocrine disturbances induced in the aunran tadpole by the early ablation of the pars buccalis of the hypophysis. erior lobeneither alters the nature of this curve nor produces quantitativeresults of unquestionable significance, although there appearsto result in most cases from this diet a small increment in sizeand a somewhat earlier completion of metamorphosis. The growth curve of albinous frog larvae with a liver-lettucediet differs in character and in magnitude from that of the nor-mals (fig. 1). I have described these changes previously (Smith,18), and later work has amply confirmed them. A retardationin growth following the appearance of albinism is unquestionedand becomes progressively greater until approximately a 30- to 2 Caselli (00), whole-gland glycerin extracts; Cerletti (01), a centrifugalizedaqueous-glycerin emulsion; Aldrioh (12), fresh desiccated non-defatted anterior-lobe substance; Aldrich (12),. fresh defatted anterior-lobe substance; Robertson(16), fresh anterior lobe and his alcoholic extract, Tethehn, of the desiccated an-terior lobe. THE PAKS BUCCALIS OF THE HYPOPHYSIS 45. Fig. 1 Growth curves of normal frog larvae supplied with a liver diet, hypophy-sectomized frog larvae supplied with liver and with fresh anterior-lobe ordinates represent the total length of the larvae expressed in millimeters. 46 PIGMENTARY GROWTH AFTER ABLATION OF 32-mm. stage (midlarval period) is reached. At this stage theretardation becomes extremely pronounced and an abrupt changein the direction of the growth curve ensues. So definite andso characteristic is this point that it appears to indicate a sig-nificant period in the development of these albinous larvae andhereafter will be designated as the critical point. Both intime and stage of development this point has been coincidentin the curves plotted from data secured in 1918 and 1919. Fromthis critical point the divergence between the curves of thenormal and albinous la
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectfrogs, bookyear1920
