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.

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.