i2 ON THE HTOID OF AliYTES OBSTETRIC AXS. [Jan. 18, 



■2. DuGES, A. — " Eecherches sur I'Osteologie et la Myologie des 

 Batraciens." Mem. (des savans e'trangers) de I'Acad. 

 des Sci., t. vi., Paris, 1835, pp. 1-216. 



3. Gavpp, E. — " Beitriige zur Morphologie des Schadels. 11. Das 



Hyo-Branchial-Skelett der Anuren und seine Urn wandhing." 

 Morph. Arbeiten (Scbwalbe), Bd. iii. Heft 3, Jena, 1894, 

 pp. 399-438. 



4. GoTTE, A. — Die Entwickeluugsgeschichte der Unke. Leipzig, 



1875. 



5. Hexle, D. J. — Beschreibung des Kehlkopfs. Leipzig. 1839. 



6. HoFFMA^'x, C. K. — Klassen und Ordnuugen des Thierreichs 



(Bronn) : Anipliibien. Bd. vi. Abth. 2. Leipzig und Hei- 

 delberg, 1873-78. 



7. Pabkee, W. K. — '■ On the Structure and Development of the 



Skull in the Batrachia. Part III." Phil. Trans. Boy. Soc. 

 vol. 172, London, 1881 (1882). 



8. RiDEWOOD, W. G. — " On the Sti-ucture and Development of 



the Hyobranchial Skeleton and Larynx in Xenopus and 

 Pipa." Journ. Linn. Soc. (Zool.), vol. xxvi., London, 1897, 

 pp. 53-128. 



9. RiDEWooD, W. G. — " On the Structure and Development of 



the Hyobranchial Skeleton of the Parsley-Frog (Pehdytes 

 punctatii^y Proc. Zool. Soc. Loud., 1897, pp. 577-595. 

 10. Staitsius, H. — Handbuch der Zootomie. Th. ii. Bucb 2. 

 Zootomie der Amphibien. Berlin, 1856. 



EXPLAIS'ATION OF PLATE IJ. 



Fig. 1. Hyobranchial skeleton of Alytes obstetrkam. Stage 1, p. 5. Dorsal 

 view. (X4^.) 



2. Same. Stage 2, p. 7. Dorsal view. (x4^.) 



3. Same. Stage 3, p. 8. Dorsal view. (x5i.) 



4. Same. Stage 4, p. 8. Dorsal view. (x6^.) 



5. Same. Stage 5, p. 9. Dorsal view, (xoj.) 



6. Same. Stage 6, p. 10. Dorsal view. (x7^.) 



7. Same. Stage 7, p. 10. Dorsal view. (x75.) 



8. Same. Stage 8, adult, p. 11. Ventral view. (x4.) 



Eeferesce Letters. 



c. Autogenous cartilages in figs. 4-6. 

 ca. Anterior copula. 

 ch 1. First ceratobranchiaL 

 c64. Fourth ceratobranchial. 

 ch. Ceratohyal. 

 cp. Posterior copula. 

 h. Hyoidean cornu. 

 hb. Hypobranchial plate. 

 hgs. Hyoglossal sinus. 

 h. Laryngeal sinus. 

 pal. Processus antero-lateralis. 

 ppl. Processus postero-lateralis. 

 j)r. Pars reuniens. 

 sp 3. Cartilaginous spiculum of the third brancbial arch. 

 t. Thyroliyal. 

 tf. Thyroid foramen, 

 r. Ventral splint-bone. 



