152 Journal of Comparative Neurology 



Fig. 4. Camera drawing of horizontal section of same. Plane of section 

 seen at C. 



Fig. jf. Pen sketch of directly lateral view of model of right nasal cavity 

 of medium-sized tadpole of leopard frog, 5 mm. long, Rana virescens ; con- 

 structed from horizontal sections, magnified 1000 diameters. A, B, C, D, and 

 E, indicate the planes of the sections shown in Figs. 1-4, Plate X, and Figs. 1 

 and 2, Plate VIII. 



Fig. 6. Pen^sketch of median view of model of right nasal cavity of still 

 older tadpole of leopard frog, Rana virescens, built up from perpendicular sec- 

 tions. Magnified 450 diameters. 



Fig. 7. Pen sketch of directly dorsal view of same. 



PLATE XI, Figs. 1-8. 



Fig. 1. Crayon sketch of dorsal view of model of right nasal cavity of 

 Salamandra atra (European salamander) ; larval, just born, 16 mm. long; mag- 

 nified 120 diameters. 



Fig. 2. Crayon sketch of ventral view of same. 



Fig. 3. Crayon sketch of dorsal view of model of right nasal cavity of 

 Hyla versicolor. Constructed from transverse sections, magnified 227 diameters. 

 This shows the three cul-de-sacs from before. 



Fig. 4. Crayon sketch of ventral view of same. 



Fig. 5. Crayon sketch of model of right nasal cavity of very young tad- 

 pole, Rana virescens; showing, even at this stage, the external and internal nares, 

 and the inner and outer diverticles. 



Fig. 6. Crayon sketch of ventral median view of model of right nasal 

 cavity of medium-sized tadpole, Rana virescens ; showing internal and external 

 nares, glands, and inner larger diverticle. Compare Fig. 5, Plate X. 



Fig. 7. Crayon sketch of directly dorsal view of model of left nasal cavity 

 of tadpole of Rana virescens, quite old, legs one mm. long. Constructed from 

 transverse sections, magnified 150 diameters. 



Fig. 8. Crayon sketch of ventral view of same. 



PLATE XII, Figs. 1-4. 



Fig. 1. Crayon sketch of lateral view of model ]of right nasal cavity of 

 Bufo lentigeninosus. Constructed from horizontal sections; magnified 80 dia- 

 meters. 



Fig. 2. Crayon sketch of median-ventral view of same. 



Fig. 3. Crayon sketch of directly dorsal view of model of right nasal cav- 

 ity of Amblystoma functatnm; constructed from transverse series of sections ; 

 magnified 400 diameters ; specimen one centimeter long. 



Fig. 4. Crayon sketch of ventral view of same showing anterior and pos- 

 terior nares. 



