Asks WDF to observe at what age pigeons have tail-feathers sufficiently developed to be counted.

CD is hard at work on his notes for a book with all the facts "for & versus" the immutability of species.

Asks for a young chicken and a nestling common pigeon.

Thanks WDF for his offer of assistance in collecting varieties of poultry. Describes his needs. He will raise his own pigeons.

Often doubts whether, despite all help, the problem of species will not overpower him.