Fragments sur la structure et les usages des glandes mammaires des cétacés

Seeking to establish a general law of animal organization, Geoffroy Saint-Hilaire focused on the lactation of marine mammals and monotremes (echidnas, platypus), their vascular systems and mammary glands.
He relies as much on the works of antiquity (Aristotle or Pliny) as on those of his contemporaries, scientists or explorers, such as Baër, Meckel, Camus, Ruisch, Owen, Duméril, Merret, Ampère or Blainville, to argue his conclusions.

Included here are several papers and memoirs presented to the Museum d'Histoire Naturelle and the Académie de Médecine, from the late 1820s onwards, in which Geoffroy Saint-Hilaire sets out his research and observations on reproduction.

Also included are copies of letters in which the scientist requests information about whales or porpoises stranded in Brittany, part of one of the two lithographed plates illustrating the printed work, with 3 pages of autograph captions, and a file, titled by him, consisting of notes on the work of German anatomists Karl von Baër and Johann Friedrich Meckel (written in another hand), as well as 9 letters addressed to him, about cetaceans observed on the Breton coast.