To William Thiselton-Dyer   16 March 1891

16./3./91.¹

By this mail, dear Mr Dyer, I send to Kew some ferns, collected on Mt Yule in New Guinea under the auspices of Sir Will Macgregor and by a party, for whose exploration the Victorian Branch of the Royal Geographic Society of Australia voted £300 - - . I planned the ascent of that mountain, the height of which is 11,000' - The results of the expedition, so far as zoologic botanic and mineralogic collections are concerned, is not considerable.

Prof. Naudin sent me just his last memoir on Eucalypts.² Entre nous I very much doubt the stability of his many new species, and he has even more yet to describe, so he just informs me, from the material of the Paris-Herbier, which has been placed at his disposal. I pointed in a tender way out to him³ some errors in this treatise, but will give him at his venerable age no pain, especially as he brings again many data of novelty and deserves great praise for his zeal. Inter alia I mentioned to him, that Correspondents in India found various Eucalypts not keeping true to the Australian types there under the different climatic conditions, and so it may be at the mediterranean Sea. It is hardly necessary to say, that the Euc. Staigeriana, which Naudin now unites with E. citriodora, was raised from wrongly named seeds of the latter. The genuine E. Staigeriana has a close affinity to E. crebra, but not to E. citriodora.

Regardfully yours always

Ferd. von Mueller

What I said about some altered growth of the Eucalypts in India, is exemplified also by the British Cardamine hirsuta and C. silvatica, when they get, as in Australia, into frostless regions.

I am now in frequent communication with Sir Th. Elder in Adelaide to get off the new Expedition Centr Australia during the cool season.⁴

This time we can hope that Leichhardts fate will be revealed.⁵

Cardamine hirsuta

Cardamine silvatica

Eucalyptus citriodora

Eucalyptus crebra

Eucalyptus Staigeriana