664 MEMOIRS OF THE CARNEGIE MUSEUM. 



EXPLANATION OF PLATE XLV. 



Gills of Diplodon imitator Ortmann, Diplodon simillimus Ortmann, Diplodon 

 vicARiiTs Ortmann, and Diplodon decipiens Ortmann. 



All figures represent the left gills magnified to twice natural size, the inner gill to the left, 



the outer gill to the right. 



Fig. L Diplodon imitator Ortmann, from Rio Vaccahy-mirim, Santa Maria, Rio 

 Grande do Sul, Brazil. Carn. Mus. Cat. No. 6L9248. 



Fig. la. Gills of male (No. 29) (Shell of this specimen figured on Plate XXXIV, 



fig. 5). 



Fig. \h. Gills of female (No. 32). 



Fig. 2. Diplodon simillimus Ortmann, from Rio Nhundiaquara, Morretes, Parana, 

 Brazil. Carn. Mus. Cat. No. 61.9250. 



Fig. 2a. Gills of male (No. 7). 



Fig. 25. Gills of female (No. 23). 



Fig. 3. Diplodon vicarius Ortmann, from creek (Rio Ribeira drainage). Aqua 

 Quente, near Iporanga, Sao Paulo, Brazil. Carn. Mus. Cat. No. 61.9251. Gills of 

 female (No. 14). 



Fig. 4. Diplodon decipiens Ortmann, from creek (tributary to Rio Iguassii), 

 Serrinha, Parana, Brazil. Carn. Mus. Cat. No. 61.9253. 



Fig. 4o. Gills of male (No. 2). 



Fig. 4b. Gills of female (No. 6) (Shell of this specimen figured on Plate XXXVI, 



fig. 4). 



