STUDIES ON EXPERIMENTAL HAPLOIDY IN SALAMANDER LARVAE

I. EXPERIMENTS WITH EGGS OF THE NEWT, TRITURUS PYRRHOGASTER

¹ From the Department of Anatomy, Medical College, Syracuse University and the Marine Biological Laboratory, Woods Hole, Massachusetts

1. Eighty seven per cent of the punctured eggs of Triturus pyrrhogaster began development.

2. Advanced haploid larvae were obtained. Nine haploid larvae developed to stages ranging from the limb bud to a swimming larva 47 days of age. One haploid-diploid larva had begun to metamorphose at the time it was fixed.

3. Advanced androgenetic larvae can be obtained more readily in Triturus pyrrhogaster than in Triturus viridescens: 27 per cent of the segmenting eggs developed beyond the gastrula stage in Triturus pyrrhogaster as compared to 10 per cent in Triturus viridescens.

4. Edema was the most common and serious abnormality associated with haploidy.

5. In the majority of cases it was impossible to reduce the edematous condition of the larvae with varying concentrations of salt solutions.

6. Two triploid larvae were obtained from punctured eggs. These larvae appeared to be entirely normal and slightly larger than the diploid larvae. This is the eighth species of amphibian in which triploidy has been observed.