. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 332 D. D. WHITNEY. determine the size and condition of the head of the spermatozoon after it had entered the egg. The egg examined was sectioned while inside the body of the female and although it had the thick secretion around it which later would have shrunken to form the heavy external covering or shell it was readily sectioned at this ?&*« -*-•. FIG. 6. Portion of a fertilized egg of Hydatina senta. E, egg nucleus containing chromosomes; 5, sperm-head; Y, yolk granules of the egg. (Sperm-head and the outline of egg n
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 332 D. D. WHITNEY. determine the size and condition of the head of the spermatozoon after it had entered the egg. The egg examined was sectioned while inside the body of the female and although it had the thick secretion around it which later would have shrunken to form the heavy external covering or shell it was readily sectioned at this ?&*« -*-•. FIG. 6. Portion of a fertilized egg of Hydatina senta. E, egg nucleus containing chromosomes; 5, sperm-head; Y, yolk granules of the egg. (Sperm-head and the outline of egg nucleus drawn to same scale as in Figs. 3-5. Yolk granules and chromosomes drawn freehand without measurements.) early stage. The sperm head is seen near the nucleus of the egg (Fig. 6). It is about the size of the head of the normal spermatozoon as can be seen by comparing it with Fig. 3, but contains denser chromatin material and is perfectly round in form. Dimorphic spermatozoa have been studied in considerable detail in some of the Mollusca and in some of the Lepidoptera by several workers. Among these Goldschmidt and Gatenby recently have come to the conclusion that the atypical or abnor- mal spermatozoa are wholly functionless and the latter is of the opinion that such spermatozoa have no significance in regard to sex regulation. According to their conclusion any spermatozoa and in some cases all spermatozoa of these forms studied may become degenerate if the male individual is in a certain physiologi- cal condition. In the phylloxerans and in the rotifers the case is quite dif- ferent. In each and every male a certain percentage of the sperm. 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 re
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
