PLATE XXXV. 
Modiomorpha concentrica. 
Page 275. 
See Plates 34, 36. 
Fig. 1. A right valve of a young- individual showing a strongly angular uinbonal ridge, a furrow along 
the middle of the cardinal slope, and the anterior muscular impression. 
Hamilton group. Delphi, N■ Y. 
Fig. 2. A somewhat larger left valve of an individual presenting characters similar to the preceding. 
Hamilton group. (Shore of Cayuga lake, N. Y. 
Fig. 3. The right side of a large individual showing the arcuate form characteristic of old individuals. 
Hamilton group. Schoharie Co., N. Y. 
Fig. 4. A left valve of medium size of very short and broad form. 
Hamilton group. Shore of Cayuga lake, N. l r . 
Fig-. 5. The interior of a left valve of a short and broad form, showing a strong tooth under the beak, with 
the anterior and posterior muscular scars and connecting pallial line. 
Hamilton group. Delphi, N. Y. 
Modiomorpha su b a lata . 
Page. 2S3. 
See Plate 39. 
Fig. 6. A right valve of an unusually short and broad specimen. 
Hamilton group. Delphi, N. Y. 
Fig. 7. A right valve of unusually elongate form. 
Hamilton group. Delphi, N. Y. 
Modiomorpha tonderosa. 
Page 271. 
See Plate 34. 
Fig. 8. The left side of a cast showing- the form and muscular scars. 
Corniferous limestone. Clarence Hollow, N. Y. 
Modiomorpha recta. 
Page 2S6. 
Fig. 9. The right side of a cast showing- the muscular scars and pallial line. 
Hamilton group. Clarke Co., Ind. 
Modiomorpha subangdlata. 
Page 2S7. 
Fig. 10. A right valve showing the anterior muscular scar. 
Chemung group. Mansfield, Pa. 
Fig. 11. A smaller right valve showing the muscular scars. 
Chemung group. Mansfield, Pa. 
