1897.] SKELETON OF PELODYTES PUNCTATUS. 593 



the ossified median constituents of the larval mandible (lower 

 labial cartilages of Parker), the outhnes of which disappeared 

 between stages 4 and 5. 



Summary. 



The almost complete closure of the hyoglossal sinus of Peloclytes 

 (Jigs., fig. 9) is due to the extensive development and inward slope 

 of the processus anteriores {pa., fig. 9). 



The lateral foramina of Peloclytes {fl., fig. 9) are not primary 

 fenestrations of the basal plate, but are formed by the enclosure 

 of the foremost lateral sinus by the confluence of the expanded 

 end of the processus antero-lateralis with the cartilage of the 

 hyoidean cornu. 



Although in Pelodytes the hyoidean cornu {h, h', h", fig. 9) is 

 broken, the portion missing is comparatively insignificant. 



The spicuia (sjj., fig, 1) are larval structures of no morphological 

 significance. They are processes of cartilage developed from the 

 proximal ends of the ceratobranchials to support the horizontal 

 pharyngeal velum. 



The processus postero-lateralis (ppl., fig. 9) is the persistent 

 proximal portion of the first ceratobranchial. 



The processus antero-lateralis {pal., figs. 8 & 9) is a secondary 

 outgrowth of the basal plate or body of the hyoid having no 

 relation whatever to the larval branchial bars. 



The thyrohyal {t., fig. 9) is the part of the hypobranchial plate 

 of the larva which forms the inner boundary of the thyroid 

 foramen {tf., fig. 4). Its posterior end becomes free on the 

 absorption of the ceratobranchials and the consequent conversion 

 of the foramen into a sinus. 



List of Authoeities eefeeeed to. 



1. BouLETiTGEE, Gr. A. — Brit. Mus. Catalogue of Batrachia Salientia. 



2nd Ed. London, 1882. 



2. Cope, E. D. " Batrachia of North America." Bull. United 



States National Museum, No. 34, 1889. 



3. Cttviee, Gr. — Eecherches sur les Ossemens fossiles, t. v. pt, 2. 



Ed. 4to. Paris, 1824. 



4. DuGEs, A. — " Eecherches sur I'Osteologie et la Myologie des 



Batraciens." Mem. de I'Acad. des Sci., t. vi., Paris, 1835, 

 pp. 1-216. 



5. Gaupp, E. — " Beitrage zur Morphologie des Schadels. II. 



Das Hyo-Branchial-Skelett der Anuren und seine Um wand- 

 lung." Morph. Arbeiten (Schwalbe), Bd. iii. Heft 3, 

 Jena, 1894, pp. 399-438. 



6. GoTTE, A. — Die Entwickelungsgeschichte der Unke. Leipzig, 



1875. 



7. HoEEMAJsrsr, C. K. — Klassen und Ordnungen des Thierreicha 



(Bronn) : Amphibien, Bd. vi. Abth. 2. Leipzig und Heidel- 

 berg, 1873-78. 



8. Meckel, J. E. — " t)ber das Zungenbein der Amphibien." 



