. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. Vol. 98, No. 1 February, 1950 THE BIOLOGICAL BULLETIN PUBLISHED BY THE MARINE BIOLOGICAL LABORATORY. CYTOLOGICAL ABNORMALITIES PRODUCED BY EXPERI- MENTAL TEMPERATURE SHOCK ON TRITURUS TOROSUS EMBRYOS * CATHERINE HENLEY University of North Carolina INTRODUCTION The importance of a complete chromosome complement in normal development is obvious when one considers the evidence that the chromosomes are the carriers of genes governing the characters of the organism. It is of considerable theoretical and practical interest to asce
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. Vol. 98, No. 1 February, 1950 THE BIOLOGICAL BULLETIN PUBLISHED BY THE MARINE BIOLOGICAL LABORATORY. CYTOLOGICAL ABNORMALITIES PRODUCED BY EXPERI- MENTAL TEMPERATURE SHOCK ON TRITURUS TOROSUS EMBRYOS * CATHERINE HENLEY University of North Carolina INTRODUCTION The importance of a complete chromosome complement in normal development is obvious when one considers the evidence that the chromosomes are the carriers of genes governing the characters of the organism. It is of considerable theoretical and practical interest to ascertain the effects of addition or loss of single chromo- somes, or of chromosome sets. Most of the early work in the field of developmental genetics was done with plants, until publication of the reports of Fankhauser (1938 and subsequent papers). These reports indicated the value of a tail-tip method for the cytological study of amphibian larvae. The technique utilized is sufficiently simple that systematic studies can be carried out on a large scale, to determine the incidence of heteroploidy in a natural population of salamander larvae. It was with the view of making such a study on Triturns torosns that investigations were begun in 1947 on larvae devel- oping from eggs which had been shipped to Chapel Hill from California, in a mixture of ice and water. These larvae showed a very high incidence of mosaic heteroploidy (43 per cent in a sample of 126 larvae), and of severe mitotic abnor- malities of various types. The results of this study will be presented in a separate paper. The possibility existed that such a frequent occurrence of mosaicism was present in a natural population, as well as in the shipped material. Cytological study of a large group of T. torosns larvae collected in nature as young embryos and raised in the laboratory indicated that this was not so (Costello and Henley, 1948, 1949). It was further demonstrated that larvae raised from eggs collected in very c
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
