PLATE X. 



1-1 RIOPECTEN PRIAMUS. 



Page ->i 



See Plate 82. 



Pig. I. A left valve, showing the form and surface characters. The figure should also show numerous fine 



raj s "ii the posterior ear. 

 Fig. -. A similar lefl valve, showing considerable variation in the surface characters, and strong liga 

 mental area with a central cartilage-pit. 



Chemung group. Franklin, Delaware Co., X. Y. 



AviCULOPECTEN STR1 vri 8. 

 Page 32 



Kg. 3. A lefl valve; tl iginal of fig. 7. p. 264, Geolog. Rept. Fourth Dist. N. V. 1843. 



Pig. i. An enlargement of the same, showing more distinctly the characters as described. 

 Chemung gronp. Painted Post, Steuben Co., N. V 



IjYRK >1'K( ' I'EX AN( > M I KF< >RMIS. 

 Page 53 

 See Plates 4 and 82. 

 Pig. .">. A left valve. This specimen i- more correctly represented on plate s-j. iig. 2. 

 Chemung group. Chemung creek, N. )'. 



liVRIOl-ECTEX XRICOST \ lis. 



Page 18. 



See Plates 4 and 7. 



Fig. 6. An imperfect left valve preserving a portion of the striated ligamental area and the cartilage pit. 



Chemung group. Chemung Co., N. ). 

 Fig. 7. A small left valve with the posterior side undeveloped from accident or natural deformity. 

 Chemung group. Near Elmira, -A'. 1". 



Fig. S. A large left valve, showing the byssal notch on the anterior side and tli iparative size of the 



anterior and posterior ears. The posterior ear in the specimen, shows several obscure rays 

 and the ligamental area is strongly striated. 



Chemung gi p. Near Elmira, N. 1". 



Pig. '.'. A fragment of a large left valve preserving a more extended posterior ear than usual. The 



anterior ear is too much extended in the figure and should be represented as in fig. 8. 

 Pig. to. A left valve with a portion broken away, showing what appears to be the right valve beneath. 

 The stronger radii should be continuous over the interval occupied 1>_\ the other valve, and 



the finer lines on thai valve should i f the same character as on the left \ alve. 



Chemung group. Broonu Co., N. P. 

 II. 12. Two small lefl valves representing the form and ornamentation of the shell at this period of 



irrou th. 



i % ' i I).. Chemung Co., N. T. 



