482 RICHARD ASSHETON. 
11. Pritznrr, W.—‘ Die Hpidermis der Amphibien,” ‘ Morphologisches 
Jahrbuch,’ vol. vi. 
12, Preyer, W.—“ Verlangerung der Embryonalzeit bei Wirbelthieren,” 
‘Jen. Zeit. f. Naturwiss.,’ 1881. 
13. Semon, R.—“ Die Entwickelung der Synapta digitata,” ‘Jen. Zeit. 
f. Naturwiss.,’ vol. xxii. 
14. Sepewick, A.—‘‘ The Original Function of the Canal of the Central 
Nervous System of Vertebrata,” ‘Studies from the Morphological 
Laboratory in the University of Cambridge,’ vol. ii. 
15. Stour, Po.— Ueber die Haftorgane der Anurenlarven,” ‘Sitzungsber. 
phys.-med. Ges. Wurzburg,’ 1881, No. 8, p. 118. 
16. Wicutman, A. C.—‘“‘On the Ventricular Epithelium of the Frog’s 
Brain,’ ‘Studies from the Biological Laboratories of the Johns 
Hopkins University,’ vol. iv. 
17. Wittny, A.—‘ Amphioxus and the Ancestry of the Vertebrates,’ 1894. 
EXPLANATION OF PLATE 35, 
Illustrating Mr. Richard Assheton’s paper, ‘‘ Notes on the 
Ciliation of the Ectoderm of the Amphibian Embryo.” 
List of Reference Letters. 
A, Anterior end of embryo. AN. Anus. BP. Blastopore. C. Ciliated 
cell. €.C. Stream of water in connection with the mucous or cement gland. 
C.GL. Mucous or cement-gland cells. C.GZ'. The necks of the mucous or 
cement cells. DG. Dorsal groove formed by the junction of the edges of 
the neural plate. 2P.2#. Epidermic layer of epiblast. #P.N. Nervous layer 
of epiblast. 1. Nasal depression. V.B.C. Naso-branchial stream. .G. 
Neural groove. JZ. Mucous or cement gland (sucker). P. Posterior end 
of embryo. P.S. Primitive streak. £&.G@. Rudiment of Gasserian and other 
ganglia of the cranial nerves. AM. Ridges, richly ciliated, bounding the 
cement-glands. S. Stomodeum. SC. Stomodzal stream. 
Fic. 1,—Surface view of the embryo of Rana temporaria. The neural 
plate is folding upwards. The arrows indicate the only area upon which 
cilia are at this time developed, and the direction of the flow of water pro- 
duced by their action. 
