BULLETIN 



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OF THE 



WISCONSIN NATURAL HISTORY SOCIETY. 



LIBRARY 



———=—======= ^=^= NEW YORK 



Vol. 8. JANUARY, 1910. No. 1 BOTANIC Al 



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PROCEEDINGS. 



Milwaukee, October 14, 1909. 



Meeting- of the combined sections. President Barth in the chair. 

 Thirty people present. Minutes of the last meeting- read and approved. 



The subject for discussion was "The Physical Nature of Death." 



Dr. Robert C. Washburn opened by speaking on The Question of 

 Natural Death Among One-celled Organisms. Dr. Washburn discussed 

 briefly Weissmann's theory, "that death among unicellular organisms 

 is ompossible, and that reproduction by fission or spores insures im- 

 mortality." In disputing this theory Dr. Washburn declared that 

 Weissmann had built on an unsound basis and quoted Maupas' experi- 

 ments with Infusoria, which the latter had bred for many generations ; 

 these organisms soon showed signs of decay, changes leading to death, 

 unless opportunity for conjugation was given. Hertwig states that 

 "part of every cell dies during fission — the macronucleus." 



Dr. P. H. Dernehl then took up the subject What Science Has 

 Taught Us Concerning Animal Death And Its Causes. He called atten- 

 tion to various cases of apparenth death, such as of hibernating- ani- 

 mals, and drying or freezing of invertebrates, the last named as 

 exhibited by the well known vinegar leech being kin to immortality. 

 Alluding to Weissmann, Dr. Dernehl said that the immortality of 

 lower forms is not applicable to higher forms of life. Death may 

 result from three varieties of causes ; namely through violence, patho- 

 logical death, and natural death — the last being death resulting from 

 old age. While the question of pathological death was not pertinent 

 to the subject under discussion, the speaker, quoting from Notnagel, 



