. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. EXPERIMENTAL HAPLOIDY IN SALAMANDER LARVAE 403 upon the extent and normality of development. There is still the possi- bility, also, that a more normal morphological condition, which was independent of chromosome numbers, was obtained in this older larva. 3. A third larva died on the 117th day and \vas preserved. It had not completely metamorphosed. It was slightly larger than any of the controls of the same stage of development, possessed no apparent mor- phological irregularities, and was normally vigorous in all its react
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. EXPERIMENTAL HAPLOIDY IN SALAMANDER LARVAE 403 upon the extent and normality of development. There is still the possi- bility, also, that a more normal morphological condition, which was independent of chromosome numbers, was obtained in this older larva. 3. A third larva died on the 117th day and \vas preserved. It had not completely metamorphosed. It was slightly larger than any of the controls of the same stage of development, possessed no apparent mor- phological irregularities, and was normally vigorous in all its reactions. No photograph was taken after the animal's death. However, in a pho- tograph taken on the 64th day (Fig. 7b) it is seen that the larva ap- peared to be anatomically perfect and, even at this time, larger than controls of the same age (Fig. 7a). All larvae had been fed the same amount of food. This larva was triploid, even though there was the suggestion that the animal had developed by means of androgenesis. The first prepara-. 8, camera lucida drawings of nuclei of epidermis cells of the haploid- diploid larva (a), of a diploid control (/>), and of the triploid larva (c). 400 X. tion of tail fin epidermis offered 4 chromosome counts, all of which could be accepted as the triploid number. All nuclei in that piece of epidermis, a few of which are shown in Fig. 8r, were larger and less numerous than the diploid nuclei of controls (Fig. 8/>). In a preliminary exam- ination of sections of the entire larva, it was possible to make 7 chromo- some counts from five different tissues (mesenchyme, cloacal epithelium, peritoneum, liver, heart). These counts were all approximately the triploid number, , from 29+ to 33 + 2 — 3 (the triploid number being 36). It would appear, then, that this larva is entirely triploid and adds the eighth species to the list of Amphibia in which triploidy has been demonstrated. - The evidence suggesting the origin of this triploid larv
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
