THE SKULL 



83 



JPmr To JN 



Pmx ^ 



Ma 



Con- 



Fii!. 63. — SkulTj of a Young 

 AxoLOTL. Ventral view. 



face Osp 



Fig. 64. — Skull of Salamandra atra 

 (Adult). Dorsal view. 



Tn..- 



Cooo 'OB 



Fig. 65. — Skull of Salamandra atra (Adult). Ventral vi^w. 



Tr, trabecula ; OB, auditory capsule ; Fov, fenestra ovalis, closed on one side by 

 the stapes [St) ; Lgt, ligament between the stapes and suspensorium ; Cocc, 

 occipital condyles ; Bp, cartilaginous basilar plate between the auditory cap- 

 sules ; Osp, dorsal tract of the occipital cartilage ; IN, internasal plate, 

 which extends laterally to form processes [TF and AF) bounding the internal 

 nostrils [Oh] ; NK, nasal capsule ; Can, nasal cavity ; Na, external nostrils ; 

 Fl, foramen for the olfactory nerve ; Z, tongue-like outgrowth (intertrabecula) 

 of the internasal -plate, which forms a roof for the internasal cavity; 

 Qu, quadrate ; Ptc, cartilaginous pterygoid ; Pot, otic process, Ped, pedicle, 

 and Pa, ascending process, of the quadrate ; Ps, parasphenoid ; Pt, bony 

 pterygoid ; Vo, vomer ; PI, palatine ; Pp, palatine process of maxilla ; Vop, 

 vomero-palatine ; Pmx, premaxilla ; M, maxilla ; Os, sphenethmoid ; An, 

 prootio ; N, nasal ; Pf, prefrontal, perforated at D for the lachrymal duct ; 

 F, frontal ; P, parietal ; Squ, squamosal ("paraquadrate," Gaupp) ; II, optic, 

 V, trigeminal, and VII, facial foramina ; Rt, point of entrance of the 

 ophthalmic branch of the fifth nerve into the nasal capsule. 



G 2 



