Horváth Géza (szerk.): A Magyar Természettudományi Múzeum évkönyve 8. (Budapest 1910)
Soós, L.: A Helix arbustorum hím csirasejtjének fejlődése
30 S D' L. SOOS the spireme begins to form. The threadlike structure of the chromatin is more evident in the following stage (Pl. VII., Fig. 12.), which is characterized by the one sided contraction of the chromatin (synapsis). The chromatin occupies one side of the nucleus, the other part remaining quite clear ; the nucleolus lies amongst the chromatin threads, near the wall of the nucleus. The one-sided contraction of the chromatin is very characteristic for the germ-cells of many animals and plants. In animals it was observed in the following forms: Coelenterata : Sycandra (?, J ÖRGENSEN), Gonionemus (BIGELOW) ; Worms : Ascaris (B RAUER, SCHABASCHNIKOFF, TRETJAKOFF), Planaria lactea (ARNOLD), Dicrocoelium lanceatum (GOLDSCHMIDT), Lumbricus (CALKINS); Annelida (VEJDOVSKY, A. and K. E. S CHREINER); Arlhropoda : Copepoda (HACKER, B ÜCKERT, L ÉRAT), Ostracoda (W OLTERECK), Peripatus (MONTGOMERY), Insects (HENKING, MONTGOMERY, PAULMIER, DE S INÉTY, B AUMGARTNER, FARMER and MOORE, STEVENS, OTTE, XOWLIN. DAVIS, MUNSON, MORSE), Spiders (WALLACE); Mollusca (BOLLES LEE, BONNEVIE, POPOFF); Ascidiae: Ciona (M ARÉCHAL ): Vertebrates: Amphioxus (M ARÉCHAL ), Fishes (MOORE. A. and K. E. S CHREINER, FARMER and MOORE, M ARÉCHAL ). Amphibians (MCGREGOR. JANSSENS, E ISEN ), Mammals (WINIWARTER). As is to be seen from this list, which does not pretend to be complete, the synapsis is a nearly general condition in germ-cells. With regard to the question, whether synapsis is a normal condition of cells, or is caused by the influence of the reagentia, opinions are very different. According to SARGANT synapsis can be observed also in living material (pollen-cells). L ÉRAT (Gl) and MEVES (73) are of the opinion that synapsis is partly a normal appearance, partly artifact, and this is the opinion of many botanists ( S TRASBURGER and his school). On the contrary VEJDOVSKY (121) decidedly holds to a natural condition; according to POPOFF (94) it is in the ovocytes of Paludina not an artifact ; according to MUNSON (84) the synapsis of the spermatocytes of Papilio ndulus is not the result of the reagentia ; according to ARNOLD (3a.) in Planaria lactea, and MORSE (83a.) in Penplaneta americana is a normal condition. Other investigators regard it as the result of the reagentia used (MCCLUNG, JANSSE S, BOLLES LEE, DAVIS, etc.). J A\SSENS (52) emphasized the fact that he found the chromatin onesidedlv contracted, only in the inner part of his preparations where the fixing fluid could not enter sufficiently, on the contrary in the outer parts he did not find synaptocytes. DAVIS (19) also refers to the fact that in the peripheral parts of his preparations he has not found the chromatin contracted. BOLLES LEE (10) states the contraction of chromatin in the male germcells of Helix pomatia to be of pathologic appearance, because he
