Thanks AD for his paper on "Morphology of the Arthropoda" [Rep. BAAS 37 (1867) pt 2: 82], a deeply interesting subject.

Suggests he examine specimens of Scalpellum.

Fritz Müller thinks CD is mistaken, but CD cannot persuade himself he was wrong in his observations on Balanidae [Living Cirripedia 2: 105].

Pleased by CD’s letter; his object was to apply CD’s principles to the reform of zoology. When this is done, it is wonderful to see how improved one’s understanding of the Crustacea (Arthropoda) becomes. Cites examples.

Thanks AD for his work. CD regrets he is not a better German scholar, but he must endeavour to understand AD’s views.

He has gone through the whole embryology of the Crustacea and has arrived at a pretty well-established genealogy of the whole class; has even tried to write a history of the whole tribe. Finds he cannot adopt the old separation of Orders in the Class; the limits between them are indistinct.

Would like to study embryology of Limulus. Asks CD’s help in obtaining a female specimen.

Outlines his proposal to establish a marine zoological station.