506 BULLETIN 34, UNITED STATES NATIONAL MUSEUM. 



Fig. 4. Amphiuma means. 



5. TypMonectes comprcssicaudus, from the Belize. 



6. BermopMs mexicanus, with the quadrate bone turned up, exposing its infe- 



rior face, and that of the quadratojugal: 4a, the quadrate in normal po- 

 sition. From Mexico. 



7. Cliondrotus tenelrosus larva, 250 mm. 



8. Chondrotus teneh'osus, adult. 



9. Amblystoma tigriimm larva ; squamosal removed. 



10. Amblystoma punctatum, adult. 



11. Hemidactyliiim scutatiim. 



12. Batrachoseps aiienuatus. 



13. GyrinopMlus porphyriticus. 



14. Plethodon glutinostis; squamosal removed. 



15. Autodax luguhris; squamosal removed. 



16. Spelerpes ruber; squamosal removed. 



PLATE XLIX. 



The relations of the quadrate, stapedial, and hyoid apparatus in Urodela and Sali- 

 entia. Figures twice natural size, with separate details larger. From Cope, Amer- 

 ican Journal of Morphology. 



Fig. 1. Desmognathus nigra, the squamosal in place; a, stapes separate and en- 

 larged. 



2. Salamandra maculata f ; the squamosal separated. 



3. Diemyciylus torosus, squamosal removed ; a, separate squamosal. 



4. Diemyctylusviridescens, three times natural size, the squamosal removed; 2a, 



the squamosal, external side ; h, apex of ceratohyal, with hyoquadrate 

 ligament. 



5. Siren lacertina -f, squamosal in place. 



6. Discoglossus pictus, partly posterior view; a, ear-bones and origin of cerato- 



hyal, enlarged. 



7. Bufo lentiginosus americanus, the squamosal removed; a, the squamosal sep- 



arate. 



8. Spea liammondii, the squamosal removed; a, the squamosal; h, the ear- 



bones. 



9. Hyla gratiosa, the squamosal removed; a, the squamosal; h, the ear-bones 



and cartilages in profile, the cartilages of the tympanum divided by ver- 

 tical section ; c, the ear-bones and cartilages undivided, external view. 



10. Xenopus ealcaratus, partly fropi behind, with squamosal in place. 



11. Stereocyclops incrassatus, squamosal in place; a, stapes and ear-bones and 



cartilages. 



12. Bana pretiosa, squamosal in place; ear-bones and vertically divided carti- 



lages. 



PLATE L. 



The quadrate, hyoid, and auditory elements. From Cope, American Journal of Mor- 

 phology, 1883. 



Fig. 1. Banavireseens, x 2; a, squamosal bone; 5, ear-bones without epistapedial ; X 4. 



2. Banavireseens, larva with hind legs, and developed fore legs concealed ; the 



skull X 2; a, the hyoid apparatus from below X 4. 



3. Bana cateshiana, advanced larva, skull, without hyoid elements, except 



ceratohyal x 3. 



4. Trimerorhachis insignis Cope ; left posterior part of skull from below, the 



mandible in place ; natural size. From the Permian bed of Texas. 



