78 



ILLINOIS BIOLOGICAL MONOGRAPHS 



(78 



Fig. 21. 

 Fig. 22. 

 Fig. 23.- 

 Fig. 24.- 

 old 

 Fig. 25. 

 Fig. 26, 

 Fig. 27, 

 c 

 ce 

 crt 

 a 

 en 

 fne 

 ins 

 le 

 hn 



EXPLANATION OF PLATE 



-Side view of model of nasal capsule of Spderpes bilineatus 46 mm. long. 

 -Side view of model of nasal capsule of Cryptohranchus alleghaniensis two weeks old. 

 -Dorsal view of model of nasal capsule of Cryptohranchus alleghaniensis five weeks old. 

 -Ventral view of model of nasal capsule of Cryptohranchus alleghaniensis three months 



— Dorsal view of model of 

 — Dorsal view of model of 

 — Dorsal view of model of 



cupola 



colimma ethmoidalis 



crista trabeculae 



comu trabeculae 



external naris 



foramen nasalis extemus 



intemasal space 



lamina externa 



lamina medialis 



nasal capsule of Necturus maculatus 25 mm. long, 

 nasal capsule of Necturus maculatus 30 mm. long, 

 nasal capsule of a young adult of Plethodon erythronotus. 



mni median nasal incisure 



pa processus antorbitalis 



ph planum basale 



pnp prenasal process 



PP pterygoid process 



pt planum tectale 



pv planum verticale 



q quadrate 



t trabeciila 



