Horváth Géza (szerk.): A Magyar Természettudományi Múzeum évkönyve 8. (Budapest 1910)
Soós, L.: A Helix arbustorum hím csirasejtjének fejlődése
304 D! L. SOÓS 12. rajz. lieg fejlettebb spermatida elülső része. BouiN-féle pikrinformol, H EIDENHAIN. 13. rajz. Spermatid» elülső része a perforatoriummal. BouiN-féle pikrinformol, H EIDENHAIN. 14. rajz. A fejlődés vége felé közeledő spermatida. Chromidiák már csak a sejt hátulsó végében vannak. BouiN-féle pikrinformol, H EIDENHAIN. 15. rajz. Majdnem teljesen fejlett spermatozoa feje. BouiN-féle pikrinformol, H EIDENHAIN. 16. rajz. Ugyanaz, mint a megelőző rajz. BouiN-féle pikinformol, H EIDENHAIN. 17. rajz. Teljesen fejlett spermatozoa testének elülső vége. FLEMMNG-féle ehrom-osmium-eczetsav (az erősebb ötszörösen higítva), H EIDENHAIN. 18. rajz. A fejlődés késői szakaszában lévő sperniatia testének hátulsó vége. A distalis centriola két egyenlő részre oszlott. BouiN-féle pikrinformol, H EIDENHAIN. The original purpose of these observations was to clear up, if possible, the mode of reduction of Helix, which has been variously explained by VOM BATH, BOLLES LEE, PROWAZEK and ANCEL. But in working, it became evident that the species used was in many respects very appropriate for making observations in the changes of plasm and chromatin during the growth period, which changes are, as I believe, more important than the reduction itself, therefore I paid particular attention to them. A short chapter is devoted to the development of the spermatozoa which also contains, I believe, some new and useful contributions. Methods. The following investigations are based upon observations made on fixed and living material. This latter was taken from the living animal, stretched as much as possible upon coverglass. A number of fixing fluids were tried, namely: Concentrated sublimate, sublimatealcohol-acetic acid mixture, PERÉNYI'S and MAYER'S fluids, BOUIN'S picricformol, and FLEMMING'S chromic-osmic-acetic mixture (weaker and stronger). The best preparations were obtained with the two last mixtures. FLEMMING'S fluid preserved all parts of the cell very well; BOUIN'S picric-formol was not less valuable than FLEMMING'S fluid, it preserved excellently the chromatic figures, but fixed insufficiently the cliromidia of the cytoplasm. MATER'S fluid was also useful, and so was in some respects sublimate and PERÉNYI'S mixture, but the preparations made with these two last mixturers were so much inferior to those made with FLEMMING'S and BOUIN'S fluids that in later preparations they have not been used. The material was imbedded in paraffin, the sections were cut into 4 to 7 mi era, generally 4. A number of staining methods have been employed, the most
