90 



ILLINOIS BIOLOGICAL MONOGRAPHS 



[90 



EXPLANATION OF PLATE 



Fig. 77. Transverse section posterior to the external naris of the adult Hyla pickeringii. 



Fig. 78. Transverse section through the lamina externa of the same animal. 



Fig. 79. Transverse section through the choana of a 9 mm. Bufo americana. 



Fig. 80. Transverse section through the fenestra naso-basalis of Bufo. 



Fig. 81. Transverse section slightly anterior to the preceding section. 



Fig. 82. Transverse section through the external naris of the same animal. 



Fig. 83. Transverse section through the muscularis process of the quadrate of Rana viridescens 



28 mm. long. 



Fig. 84. Transverse section through the pons ethmoidalis of the same animal. 

 Fig. 85. Dorsal view of model of the nasal capsule of a young adult of Rana viridescens. 

 Fig. 86. Side view of model of the nasal capsule of the same animal. 



amp anterior maxillary process le 



anc alinasal cartilage ntpq 



cc cavum cranii no 



ce columna ethmoidalis oc 



ch choana on 



cr s crista subnasalis pb 



or t crista trabeculae pe 



fen nb fenestra naso-basalis pp 



fon foramen orbito-nasalis pt 



fs frontal branch of superficial pv 



ig intermaxillary gland qe 



ipc inferior prenasal cartilage sa 



jo organ of Jacobson spc 



Id lacrimal duct / 



lamina externa 



muscularis process of quadrate 



nasal organ 



oblique cartilage 



olfactory nerve 



planum basale 



pons ethmoidalis 



pterygoid process 



platum tectale 



planum verticale 



quadrato-ethmoidalis 



solum anterius, 



superior prenasal cartilage 



trabecula 



