We have already accounts of the development of the Müllerian ducts of reptiles from Braun (1), Mihalkovics (2), Hoffmann (3), and Wiedersheim (4). All of these writers agree in saying that the Müllerian ducts arise quite independently of the segmental ducts; but in view of recent attempts to show that in the other groups of vertebrates there are forms in which the Müllerian ducts are derived from the segmental ducts, it seemed expedient to reconsider this conclusion, and I have accordingly examined the development of the ducts in Crocodilus biporcatus, Chelone viridis, and Lacerta agilis.

As regards the derivation of the Müllerian ducts from cœlomic epithelium, I can only confirm the above-mentioned authorities; but I am able to supplement what they say as to the first foundation and the formation of the anterior end. I find that the anterior end is formed in reptiles, very much as in amphibians, by a modification of the cœlomic epithelium in the region of the pronephros. Backward growth proceeds independently alike of the segmental duct and of the epithelium of the body-cavity posterior to the ostium abdominale.