254 ALICE JOHNSON AND LILIAN SHELDON. 



21. Spenceb, W. B. — "Some Notes on the Early Development of Kana 



temporaria," this Journalj supplement, 1885. 



22. WlJHE, T. W. VAN. — " Ueber die Mesodermsegmente u. d. Entwicklung 



der Nerverf des Selaohierkopfes," 'Konigliche Akad. v. Wiss. zu 

 Amsterdam,' 1882. 



23. Durham, H. E. — "Note on the Presence of a Neurenterio Canal in 



Kana," ' Quart. Journ. Mior. Sci.,' June, 1886. 



EXPLANATION OP PLATES XXIV, XXV, and 

 XXVL 



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 Eigs. 1, 2, and 3, which were 

 drawn with obj. b, oo. 2 ; Figs. 6 and 7 with obj. c, oc. 2 ; and Eigs. 4, 5 

 and 30 with obj. c c, oo. 2. Eig. 12 was drawn with obj. a, oo. 2, and after- 

 wards reduced by one half; and Eigs. 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. 

 AuA. Ear. Bl. Blastopore. Ch. Notoobord. F. Awd. rt. Root of Eacio- 

 auditory nerve. F. B. Eore-brain. F. 0. Eore-gut. Oass. Gasserian gang- 

 lion. 0. VII, Ganglion of 7th nerve. (?. IX. Ganglion of 9th nerve. 

 H. B. Hind-brain. H. Q. Hind-gut. Inf. Infundibulum. Lat. 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 corre- 

 sponding to 7th nerve. Lat. IX. Thickening of nervous layer of epiblast to 

 form sense organ corresponding to 9th nerve. 31. B. Mid-brain. Mes. Meso- 

 blast. N. C. Neural ridge. Olf. Olfactory epithelium. 0. V. Optic vesicle. 

 P. a. g. Post-anal gut. Vit. Pituitary body. Sp. c. Spinal cord. St. Sto- 

 modseum. Thai. Thalamencephalon. Thi/. Thyroid body. V. C. I. Eirst 

 visceral cleft. V. C. II. Second visceral cleft. III. Third nerve. V. Eifth 

 nerve. VII. Seventh nerve. IX. Ninth nerve. Ill rt. Root of 3rd nerve. 

 V rt. Root of 5th nerve. Flirt. Root of 7th nerve. VIII rt. Root of 

 8 th nerve. IX rt. Root of 9th nerve. V d. Dorsal branch of 5th nerve. 

 VII d. Dorsal branch of 7th nerve. IX d. Dorsal branch of 9th nerve. 



