. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. All figures are redrawn from free-hand sketches. In the unfertilized egg the vitelline membrane is not indicated separately from the egg surface as doing so would exaggerate the real appearance. FIGS, i TO 5. Five stages in the normal fertilization reaction in Strongylocen- trotus franciscanus. Note progress of the fertilization reaction from the initial place. In 5 the reaction is not yet quite complete as the egg is still slightly excentric within the membrane. FIGS. 6 TO 8. Permanent stages of partial fertilization from a
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. All figures are redrawn from free-hand sketches. In the unfertilized egg the vitelline membrane is not indicated separately from the egg surface as doing so would exaggerate the real appearance. FIGS, i TO 5. Five stages in the normal fertilization reaction in Strongylocen- trotus franciscanus. Note progress of the fertilization reaction from the initial place. In 5 the reaction is not yet quite complete as the egg is still slightly excentric within the membrane. FIGS. 6 TO 8. Permanent stages of partial fertilization from a subnormal lot of eggs of 5. franciscanus. In eggs favorably placed for such observation it has been determined that the point on the egg from which the fertilization changes take their origin is the place to which the successful sperm is attached. This has also been ascertained by so many previous observers, to whom reference will be made shortly, that it seems superfluous to dwell upon the fact. The fertilization reaction begins at the point of contact of sperm and egg and from this point is transmitted in all directions over the surface of the egg- The fertilization reaction is essentially the same in all three species studied. The chief difference between the urchin egg and the starfish egg is that in the former the membrane where it first separates from the egg elevates at once in this region to its. 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
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
