CILIATION OF ECTODERM OF AMPHIBIAN EMBRYO. 481 
eggs under conditions similar to those of amphibian develop- 
ment, one would certainly expect to find a ciliated ectoderm. 
I do not know whether this is the case in Petromyzon, in 
Ganoids, or Ceratodus. 
In connection with Sedgwick’s theory of the respiratory 
nature of the neural groove, it is interesting to find that the 
neural groove is not ciliated as long as it remains open to the 
exterior. As stated above, I have not determined at what 
time it becomes ciliated. Certainly I have never succeeded in 
seeing cilia in sections of the neural tube at any stage of tad- 
pole life. 
CAMBRIDGE ; 
June, 1895. 
List oF LITERATURE REFERRED TO. 
1. Batrour, F. M.—‘A Treatise on Comparative Embryology,’ second 
edition, 1885. 
2. Carrier, J.—‘ Die postembryonale Entwickelung der Epidermis des 
Siredon pisciformis,” ‘ Arch. f. mikros. Anat.,’ vol. xxiv. 
3, Cuarke, 8S. F.—‘‘ Development of Amblystoma punctatum,” 
‘Studies from the Biological Laboratory of the Johns Hopkins 
University,’ vol. ii, 1880. 
4. Hyciesuymer, A. C.—‘‘ The Early Development of Amblystoma, with 
Observations on some other Vertebrates,” ‘Journal of Morphology,’ 
vol. x. 
5. Garstanc, W.—“ Preliminary Note on a New Theory of the Phylogeny 
of the Chordata,” ‘ Zoologischer Anzeiger,’ vol. xvii. 
6. Kirn, E.—“ Histological Notes,” ‘Quart. Journ. Micr. Sci.,’ vol. xx. 
7. Marsuatt, A. M., and Buus, HE. J.—‘‘ The Development of the Blood- 
vessels in the Frog,” ‘Studies from the Biological Laboratories of 
the Owens College,’ vol. ii. 
8. Morean, T. H.—‘‘On the Amphibian Blastopore,” ‘Studies from the 
Biological Laboratory of the Johns Hopkins University,’ vol. iv. 
9. Morean, T. H.—‘‘The Growth and Metamorphosis of Tornaria,” 
‘ Journal of Morphology,’ vol. v. 
10. Oszorn, H. F.—Preface to ‘Amphioxus and the Ancestry of the Verte- 
brates,’ by Willey. 
