Note 267 — Part III. ON THE FINAL CAUSES OF TRANSFORMATION.

[This species is interesting as being ovoviviparous, the young passing through the branchiate stage within the body of the mother. Some experiments, which were partially successful, were made by Fräulein v. Chauvin with a view to solve the question whether the branchiate stage could be prolonged by taking the larvæ directly from the mother before birth and keeping them in water. See “Zeit. für wissen. Zoo.” vol. xxix., p. 324. R.M.]