. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 356 ROBERT CHAMBERS a specific attraction such as Fol suggested. I may cite, for example, a case in which about 30-50 spermatozoa were blown on the surface of an egg. Most of the spermatozoa immediately became attached to a restricted region on the outer border of the jelly. One, however, wandered off a short distance and suddenly a cone appeared with a ,- •,,.,- , i y, • - ^•..\>'1' !"]"><•' •' '- ».-^^^]r^^Lj^.\-'.'^. V/;-^ '&.**. V;v FIG. 11 FIG. 12 FIG. 11. Polyspermy in an egg 5 ho
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 356 ROBERT CHAMBERS a specific attraction such as Fol suggested. I may cite, for example, a case in which about 30-50 spermatozoa were blown on the surface of an egg. Most of the spermatozoa immediately became attached to a restricted region on the outer border of the jelly. One, however, wandered off a short distance and suddenly a cone appeared with a ,- •,,.,- , i y, • - ^•..\>'1' !"]"><•' •' '- ».-^^^]r^^Lj^.\-'.'^. V/;-^ '&.**. V;v FIG. 11 FIG. 12 FIG. 11. Polyspermy in an egg 5 hours old. The egg nucleus and two polar bodies show prominently in the middle of the figure. Sperm at x, although more advanced, entered later than sperm at y. FIG. 12. Polyspermy in an immature egg. tenuous filament extending to the spermatozoon diagonally through the jelly. The filament then retracted with the spermatozoon on its tip and insemination resulted. 4. Insemination of Immature and of Aged Eggs Eggs aged by standing in sea-water lose their protective reaction against polyspermy. Fig. 11 represents an egg which was inseminated after it had been standing in sea-water for five hours, which is over four hours longer than is usual for normal fertilization. Within one minute numerous cones formed on the egg. The figure shows the egg with six attached spermatozoa, all of which were taken in. Owing to the rapidity of the procedure and the variations in the angles of direction which the filaments take, it was impossible to ascertain whether or not the cones in the figure which show no filaments did in reality possess filaments with spermatozoa attached to them. There is often a lack of uniformity in the sequence of the sperm entries. In Fig. 11 the spermatozoon at x was in advance of its neighbor at y. In spite of this, spermatozoon y entered before x. One egg, two hours after maturation, formed two cones with in-. Please note that these images are extracted from s
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