Fig. I. 



The skull and vertebral column of the Frog, viewed from the dorsal surface. 

 B^ The same from the ventral surface. C, Lateral view of the urostyle ; a bristle 

 is passed through the foramen for the tenth spinal nerve. D, The branchial 

 skeleton of the Frog. (AH the figures after Ecker.) O, orbital fossa; pnix, 

 premaxilla ; vix, maxilla ; g-j, quadrato-jugal ; na, nasal ; fif, parieto frontal ; 

 rfx, exoccipital ; fr}i^ foramen magnum ; pro^ pro-otic ; sg, squamosal ; sp. et, 

 sphenethmoid ; par, parasphenoid ; pal, palatine ; vo, vomer ; ptg; pterygoid ; 

 av, atlas vertebra; c, centrum; ar, neural arch; zyg; zygapophysis ; trv, trans- 

 verse process ; ur, urostyle ; H, body of the hyoid ; Ha, anterior cornu ; Hp, 

 posterior cornu of the hyoid. 



Digitized by Microsoft® 



