334 SCIENCE PROGRESS. 



It follows thus, that if the inferences I have drawn from 

 these indisputable facts of histology are correct, that the 

 synapsis should, and probably will, be found somewhere 

 in the infusorial life cycle of to-day. Unfortunately the 

 character of the nuclei of the Infusoria, the lack of the 

 appreciation of the importance of such phenomena as I have 

 just described, and more than anything, the Weismannistic 

 conception of animal reduction, based as it is on O. Hertwig's 

 erroneous observations, have hitherto left us in the dark 

 concerning the existence or the non-existence of a synapsis 

 in these forms. I have no doubt that with the modern 

 methods of observation, we shall be able some day to pro- 

 nounce definitely on the matter, and the knowledge, when 

 it does come, will throw a most important light on future 

 biological research. 



BIBLIOGRAPHY. 



1) GRUBER. Uber Kerntheilungsvorgange bei einigen Protozoaen. 

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2) GRUBER. Eine Mittheilung liber Kernvermehrung und 

 Schwarmerbildung bei Siisswasser-Rhizopoden. Freiburg 

 NaturforscJiende Gesellschaft,p. 114, 1889. 



3) SCHEWIAKOFF. Uber dei Karyokinetische Kerntheilung der 

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7) BRAUER. Zur Kenntniss der Spermatogenese von Ascaris 

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8) MOORE. Mammalian Spermatogenesis. Anat. Anz., 1893. 

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10) FARMER. Uber Kerntheilung in Li Hum Antheren besonders 

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11) HERTWIG, O. Vergleich der Ei- und Samenbildung bei 

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J. E. S. Moore. 



