Although absent from the May 1866 Manifest, the typical header on the Manifest reads something like this one from July of the same year.
I, H.A.J. Neynaber Master of the Bremen SS Bremen do solemnly, sincerely and truly swear that the following List or Manifest subscribed by me, and now delivered by me to the Collector of Customs of the Collection District of New York, is a full and perfect list of all passengers taken on board of the said Steamship at Bremen from which port said Steamship has now arrived; and that on said List is truly designated the age, the sex, and the occupation of each of said passengers, the part of the vesssel occupied by each during the passage, the country to which each belongs, and also the country of which it is intended by each to become an inhabitant; and that said List or Manifest truly sets forth the number of said passengers who have died on said voyage, and the names and ages of those who died. So Help me God.
Sworn to this 2nd of July 1866