PLATE XCI. 



c — Rostrata. 

 Lepto I ) ESM A Bito jj . 



Page 222. 

 I g 1 An imperfect left valve of this speci< 



Chemung group. Smith of Smethport, Pa. 



Leptodesma aliforme. 



Page 22 ! . 

 S •■ Plate 22. 

 Fig. 2. A. large right valve |showing the pallial line and muscular impression. This figure is given in 

 ■ •(irri-rtii.il ol Kg. 2S of plate 22. 



Chemung group. Angelica, N. V. 



Leptodesma RODE. 



FitgeSZli 

 See Plate 25. 

 Fig. :{. The left valve described. This figure is given in correction of figure 12, plate 25. 

 Chemung group. Near Sinetlvport, Pa. 



Leptodesma Jason. 



Page 213. 

 Fig. 4. A left valve of the medium size. 



■ ; i rnung group. Canton, Bn , Pa. 



Fig. 5. A right valve somewhat Lmperi reserving the form of the body and cai'dinal expansions. 



Chemung group. Near Mansfield, Pa. 

 Fig. 6. A smaller right valve associated with the preceding 



Leptodesma Lesleti. 



Page 223. 

 Fig. 7. A large left valve showing the form and surface markings. 

 , * Chemung group. Susquehanna Co., Pa. 



Leptodesma avifobme. 



Page 224. 

 Fig. 8. An imperfect left valve. 



Chemung group. Tioga Co;., Pa. 



d — Patulata. 

 Leptodesma flaccidum. 



Page .'Jo 

 Pig. 9. A left valve showing the characteristii hespecies. 



Chemung group. / Fioga Co., Pa. 



Leptodesma patulum. 



Page ■-' 

 Fig. 10. An imperfect left valve. 



Chemung group. Mansfield, Pa. 

 Fig. 1 1. A right valve. 



Chemung group. \fa isfield, Pur, 



e — Arcoidea. 

 Leptodesma arcifokMe. 



Page 829 

 Fijf. 12. A large left valve. 



Chemung group. Mansfield, Pa. 



