Thanks to CD’s help Zoological Station has passed a crisis and is now flourishing.

Is writing pamphlet on "the origin of vertebrates and the principle of succession of functions" [see 9991 and 10003]. It is likely CD will not be pleased with it, but he thinks he must now, after seven years, bring it out. Seeks to open the way for a new series of theoretical questions.

The Zoological Station has already resulted in "capital work" by F. M. Balfour and Ray Lankester. G. J. Romanes is coming next year.

CD will be interested in AD’s ancestry of vertebrates. "I shall be very sorry to give up the ascidians."

Thanks AD for his Ursprung [der Wirbelthiere (1875)], which astonished CD. AD’s views, if accepted by competent authorities, will show how much we have to learn about the history of every animal. Suggests caution on "degradation principle". Comments on other views in the work. Has long seen importance of the principle of "Functionswechsel" [transfer [change!?] of function], but never enunciated it as a distinct principle.

AD is aware of revolutionary character of his pamphlet [Ursprung der Wirbelthiere]. Authorities will not agree with him. Carl Gegenbaur and Ernst Haeckel are opposed. Younger biologists are disposed to accept his views. All he can expect is to put a stop to "the Amphioxus–Ascidian affair, and to open a road for speculation and for investigation on the side of the Annelid-homology".

Regrets he is too busy to accept CD’s invitation to visit Down, but could only thank him again for saving the Zoological Station from shipwreck.

Thanks AD for the handsome Annual Report of the Zoological Station (1878). Rejoices at its success and its great service to science.