. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. a f> c d c f g ' FIG. 2. Series of sand-dollar embryos (constriction forms) developed 27 hours in M/i6o LiCI. Ectoderm (above) separated at dashed line from cnd"'k-im. Mcsenchyme packing the blastocoels omitted. The ectodermal (thin-wall, .h component, larger in a-c, is reduced in size in d-f, and nearly obliterated in >;, \\liu li is practically a holentogastrula. nuclei, etc. From a study of the lineage of cells from the pie- men ted and nonpigmented zones of the early egg it may be stated quite positively that
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. a f> c d c f g ' FIG. 2. Series of sand-dollar embryos (constriction forms) developed 27 hours in M/i6o LiCI. Ectoderm (above) separated at dashed line from cnd"'k-im. Mcsenchyme packing the blastocoels omitted. The ectodermal (thin-wall, .h component, larger in a-c, is reduced in size in d-f, and nearly obliterated in >;, \\liu li is practically a holentogastrula. nuclei, etc. From a study of the lineage of cells from the pie- men ted and nonpigmented zones of the early egg it may be stated quite positively that entoderm grows at the expense of ectoderm, some of whirh becomes converted into entoderm (and possibly aUo into mesenchyme). I ill in the solution many of these constriction forms show early death and gradual disintegration, sometimes of the eetoderm, or of both extremes, but usually of the entodermal component from its free end towards the lied 1o in .mother way: if the con- stricted gastrulae are removed early from the lithium and allowed to recover in sea water ectoderm and entoderm tend to separate from each other, especially when the two eoinpoiieiii^ are of nearly equal size (Fig. 3, v). It would ,-eeni that equality and duality are inconsistent with development of mie individuality! N/l6o is close to the optimal concentration for producing the most striking lithium effects in thi> >perie-. Retardation of. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Marine Biological Laboratory (Woods Hole, Mass. ); Marine Biological Laboratory (Woods Hole, Mass. ). Annual report 1907/08-1952; Lillie, Frank Rattray, 1870-1947; Moore, Carl Richard, 1892-; Redfield, Alfred Clarence, 1890-1983. Woods Hole, Mass. : Marine Biological Laboratory
Size: 2574px × 971px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
