NATURAL SCIENCES OF PHILADELPHIA. 235 



Fig. 6. Zonites capnodes, W. G. B. 



a. Central and first lateral. 



b. Marginal teeth. 

 Fig. 7. Zonites fuliginosus, Griff. 



a. Central and first lateral. 



b. Third marginal from edge of lingual membrane. 



Plate III. 



Fig. 1. Zonites gularis, Say. 



a. Central and first lateral tooth. 

 6. Marginal tooth. 



Fig. 2. Zonites sculptilis, Bland. 



b. Extreme marginals. 

 Fig. 3. Zonites limatulus, Ward. 

 Fig. 4. Zonites capsella, Gould. 

 Fig. 5. Zonites Elliotti, Redf. 



b. An extreme marginal. 

 Fig. 6. Zonites deraissus, Binn. 

 Fig. 7. Zonites lasmodon, Phillips. 



c. Last marginal but three. 

 Fig. 8. Zonites intertextus, Binn. 

 Fig. 9. Zonites interims, Say. 



b. The 16th and 17th tooth. 



c. The 25th tooth. 

 Fig. 10. Zonites Gundlachi, Pfr. 



6. A group of marginals. 

 Fig. 11. Zonites ligerus, Say. 

 Fig. 12. Zonites capnodes, W. G. B. 

 a, 6, c, d. The base of attachment. 

 e. The reflection. 

 /",/. The obsolete side cusps. 

 g, g. The side cutting points. 

 h. The central cusp. 

 i. Central cutting point. 



Plate IV. 

 Fig. 1. Limax flavus, Lin. 



a. Central and first lateral teeth. 



b. Marginal tooth before the bifurcation commences. 



c. An extreme marginal, to show the bifurcation of the 



marginals. 



