Text Online
From:
Darwin, W. E.
To:
Darwin, Emma
Date:
7 October [1878]
Source of text:
DAR 210.5: 27
Summary:
No summary available.
Contributor:
Darwin Family Letters
No summary available.
Thanks for pt 4 of Australian orchids [1874–].
Botanical evidence is against F. B. White’s origin of St Helena fauna. JDH holds flora is S. African. Since plants must arrive before insects, if fauna is Palearctic then flora survived glacial period. Flora not Miocene since old and relic orders are absent. Suggests S. African west coastal mountains as insects’ origin.
Suggests that benzoic acid would be a deadly poison to bacteria and their allies.
Is puzzled about the use of borax as a disinfectant because in his experiments Drosera were not in the least injured by boracic acid.