586 ALICE JOHNSON AND LILIAN SHELDON. 
21. Spencer, W. B.—“Some Notes on the Early Development of Rana 
temporaria,” this Journal, supplement, 1885. 
22. Wise, T. W. van.—‘ Ueber die Mesodermsegmente u. d. Entwicklung 
der Nerven des Selachierkopfes,” ‘ Koénigliche Akad. v. Wiss. zu 
Amsterdam,’ 1882. 
EXPLANATION OF PLATES XXXIV, XXXV, ann 
XXXVI, 
Illustrating Alice Johnson’s and Lilian Sheldon’s Paper 
“On the Development of the Newt (Triton cristatus).” 
All the figures represent single sections. They were drawn with a Zeiss’s 
camera lucida and Zeiss’s obj. A, oc. 2, except Figs. 1, 2, and 3, which were 
drawn with obj. B, oc. 2; Figs. 6 and 7 with obj. c, oc. 2; and Figs. 4, 5 
and 30 with obj. c c, oc. 2. Fig. 12 was drawn with obj. a, oc. 2, and after- 
wards reduced by one half; and Figs. 13, 16, 17, 18, 36, 37 and 38 were 
drawn with obj. a, oc. 2, and afterwards reduced by one third. 
N.B.—Grey denotes epiblast, and organs derived from it; brown denotes 
mesoblast ; and yellow denotes hypoblast, and organs derived from it. 
Alphabetical List of Reference Letters. 
Aud. Kar. Bl. Blastopore. Ch. Notocbord. F. Aud. rt. Root of Facio- 
auditory nerve. F, &. Fore-brain. F. G. Fore-gut. Gass. Gasserian gang- 
hon. G. VII. Ganglion of 7th nerve. G. ZX. Ganglion of 9th nerve. 
H. B. Hind-brain. H. G. Hind-gut. Inf Infundibulum. Jat. V. Thicken- 
ing of nervous layer of epiblast to form sense organ corresponding to 5th nerve. 
Lat. VII. Thickening of nervous layer of epiblast to form sense organ eorre- 
sponding to 7th nerve. Lat. JX. Thickening of nervous layer of epiblast to 
form sense organ corresponding to 9th nerve. J.B. Mid-brain. Mes. Meso- 
blast. WV. C. Neural ridge. O/f Olfactory epithelium. O. V. Optic vesicle. 
P.a.g. Post-anal gut. Pit. Pituitary body. Sp.c. Spinal cord. S¢. Sto- 
modeum. Thal. Thalamencephalon. Thy. Thyroid body. V. C. JZ. First 
visceral cleft. V.C. IZ. Second visceral cle!t. JIZZ. Third nerve. V. Fifth 
nerve. VJJ, Seventh nerve. LX. Ninth nerve. //7 ré. Root of 3rd nerve. 
V rt. Root of 5th nerve. Vi rt. Root of 7th nerve. VIII rt. Root of 
Sth nerve. JX rt. Root of 9th nerve. Vd. Dorsal branch of 5th nerve. 
Vi d. Dorsal branch of 7th nerve. JX d. Dorsal branch of 9th nerve, 
V sup. maz. Superior maxillary branch of 5th nerve. V inf. max. Inferior 
