. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. MORGAN. [VOL. I. It seemed possible, at least, that new tissue, composed of cells derived from two species, might show the influence of its dual origin. Harrison1 has shown that the tails of young tadpoles may be interchanged even when two species are used, and that later the ectoderm of the body of the larger component grows out over the base of the grafted tail, slipping over the region where the tail has been grafted on, as shown in Fig. i. If two species be used, and then, after the tail has grown to the stage shown in t
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. MORGAN. [VOL. I. It seemed possible, at least, that new tissue, composed of cells derived from two species, might show the influence of its dual origin. Harrison1 has shown that the tails of young tadpoles may be interchanged even when two species are used, and that later the ectoderm of the body of the larger component grows out over the base of the grafted tail, slipping over the region where the tail has been grafted on, as shown in Fig. i. If two species be used, and then, after the tail has grown to the stage shown in this figure, the tail be cut off just distal to the point of union, as shown in Fig. 2 by the vertical line, there will be present at the exposed end two kinds of tissue-- the ectoderm, which is the same as that covering the body of the tadpole, and the inner tissue, composed of muscles, connective tissue, pig-. FIG. i. (After Harrison.) ment cells, notochord and nerve cord, that belong to the grafted tail. Under these circumstances the new tail that regenerates will be made up of parts of two species. Harrison carried out an experiment of this sort. He writes2 in regard to the result : " The tail of a larva of R. virescens was replaced by the tail of a larva of R. palustris, in the manner described above. Forty-eight hours later, at which time the sketch was made (see Fig. i), the tail was amputated. The epidermis from the virescens body had then pushed out considerably over the root of the tail, so that in cutting, almost all of the grafted epider- mis (stippled in the figure) was removed. But a considerable portion of the underlying organs of the transplanted piece (shaded in the figure) remained, and it was from this compo- nent that regeneration took place in all the tissues, with the exception of part of the epidermis. The newly grown tail was 1 Harrison, R. G., "The Growth and Regeneration of the Tail of the Frog Larva," Roux's Archiv. Vol. vii, 1898. ~ Pag
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
