. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 136 ROBERT CHAMBERS, JR. The giant nuclei attain their greatest size in testes which are composed almost entirely of islands of spermatocytes in the various stages of maturation but in which no lumen yet exists. Simultaneously with the growth of the giant cell the nucleus and noticeably the nucleolus increase in size. A change also takes place in the staining reaction of the nucleus. The chro- matin network, which hitherto together with the nucleolus stained red writh safranin, loses that capacity and takes up light green, a
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 136 ROBERT CHAMBERS, JR. The giant nuclei attain their greatest size in testes which are composed almost entirely of islands of spermatocytes in the various stages of maturation but in which no lumen yet exists. Simultaneously with the growth of the giant cell the nucleus and noticeably the nucleolus increase in size. A change also takes place in the staining reaction of the nucleus. The chro- matin network, which hitherto together with the nucleolus stained red writh safranin, loses that capacity and takes up light green, an acid stain. A well-grown giant cell thus pos- sesses a large nucleus with an enor- mous basic staining nucleolus and an acid staining nuclear network, the granules in the surrounding cyto- plasm staining red with safranin. Similar cells have been described, in literature on spermatogenesis, as • rudimentary ova. A significant fact, FIG. 2. however, which militates against such an interpretation, at any rate for the giant cells in the Simocephalus testis, is that they grow directly from spermatogonia and do not pass through the synapsis stage. The striking but superficial resemblance between these giant cells and growing oocytes is evidently due to the one function common to both, viz., that of an enormous growth in size. The ever-increasing size of the nucleolus during growth and its final dissolution in both types of cells favors the assumption that the nucleolus is intimately connected with cell growth. In the spermatocytes in Simocephalus where no growth occurs the spermatogonial nucleolus remains small during synapsis and early disappears. The same is true for Pandarus1 and for Cyclops? On the other hand, in spermatocytes wrhere growrth does occur, a growing nucleolus is described by Schmalz3 in an Ostracod. In this form the nucleolus grows during synapsis and during the sub- sequent growth period to disappear on the formation of the spindle for the first maturation div
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