78 ILLINOIS BIOLOGICAL MONOGRAPHS [78 
EXPLANATION OF PLATE 
Fig. 21.—Side view of model of nasal capsule of Spelerpes bilineatus 46 mm. long. 
Fig. 22.—Side view of model of nasal capsule of Cryptobranchus alleghaniensis two weeks old. 
Fig. 23.—Dorsal view of model of nasal capsule of Cryptobranchus alleghaniensis five weeks old. 
Fig. 24.—Ventral view of model of nasal capsule of Cryptobranchus alleghaniensis three months 
old. 
Fig. 25.—Dorsal view of model of nasal capsule of Necturus maculatus 25 mm. long. 
Fig. 26.—Dorsal view of model of nasal capsule of Necturus maculatus 30 mm. long. 
Fig. 27.—Dorsal view of model of nasal capsule of a young adult of Plethodon erythronotus. 
c cupola 
ce columna ethmoidalis ° 
ort crista trabeculae 
ct cornu trabeculae 
en external naris 
fne foramen nasalis externus 
ins internasal space 
le lamina externa 
ln lamina medialis 
mnt 
median nasal incisure 
processus antorbitalis 
planum basale 
prenasal process 
pterygoid process 
planum tectale 
planum verticale 
quadrate 
trabecula 
