His gratitude for CD’s gift. An account of his difficulties with the Zoological Station and his health.

F. M. Balfour has told him that CD would like to see the question of complemental males in cirripedes studied again. AD would like to enter the field and to study the whole morphological development of cirripedes.

Describes the interest in embryological work in Russia and Germany.

THH sends to AD a draft, prepared by himself and CD, of a statement for a subscription fund to assist AD’s Naples Zoological Station.

Has written to J. Murray to have account of the Zoological Station inserted in the Murray guidebook.

The circular about the Station has been printed; some have already signed.

Received R. Kossman’s paper on Anelasma ["Untersuchungen über die durch Parasitismus hervorgerufenen Umbildungen in der Familie der Pedunculata", Verh. Phys.-med. Ges. Würz. N. F. 5 (1874): 129–57]. The case is the most interesting ever recorded of gradation, i.e., from an animal with a stomach to one with roots like a plant.

Delighted he will examine the complemental males of Scalpellum.

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.