17 St. Maurice and Claiborne Pelecypoda 17 



Anomia lisbonensis, PI. n. Figs. 6-10 



H. ephippioidesvix. lisbonensis Aid. Bull, i, Geol. Surv. Ala., tSS6, p. 



41, pi. 4, fig. 6. 

 A. lisbofiensis Ball, Trans. Wag. &c, vol. 3, 1898. p. 781. 



Aldrich' s characterization of lisbonensis. — "Shell thin, pearly, siibor- 

 bicular ; iipper valve smooth, slightly wrinkled on the umbo ; lines or grovv th 

 distant; hinge line doubly sigmoid, the extremities winged. Muscular scars 

 indistinct. 



Locality. — Lisbon and beds at base of Claiborne Bluff. 



The type is externalh' marked with broad radiating bands of color. 

 On comparison with A. ephippoides Gabb, it appears much larger and more 

 transverse ; that species is not smooth externally, and is often plicate. It 

 occupies the same horizon however. ' ' 



We have several good specimens of the larger valve of this 

 form from these t3-pe localities, some of which are shown b}^ the 

 figures, 6, 7, 8. We would not be at all surprised if some of the 

 more radiately marked specimens, from the I^isbon vicinitj^ are the 

 same as Conrad's A. jugosa although he labelled the t3^pe of that 

 species (now in the Academy's collection) from the "White 

 Limestone of South Carolina," The interior of that specimen 

 seemed to us more like hard graj^- marl than "white limestone." 

 Conrad's figure oi jugosa shows the feeble ribs much too distinct- 

 ly. They are remarkable for showing a down-bowing of the lines 

 of growth as they pass over the obscure costse. 



As remarked above, the pustulose specimens of Anojiiia in our 

 collections are Texan . The markings in lisbonenis^ besides con- 

 centric lines of growth consist generally of microscopic hachures 

 as shown by figure 9. There is, too, a slight tendency to show 

 interrupted radial foliation. Figs. 9, 10 are from the same local- 

 itj^ in N. W. Louisiana, Hammett's Branch. Fig. 10 shows how 

 even here there is a tendency for the otherwise lisbonensis to be- 

 come slightly pustulose in places. 



Type. — Aldrich Coll., now at Johns Hopkins Univ. 



Horizon. — St. Maurice Eocene. 



Specimens figured. — Geol. Mus., Cornell Univ. 



Localities. — Common in Texas with ephippioides ; Mt. Leban- 

 on — Hammett's Branch, Natchitoches, Chestnut, in Louisiana; 

 Lisbon and base of bluff at Claiborne, Ala. Thin, delicate spec- 



