28 BuivLETiN 31 28 



,^^.___.^: ....- c <^x . . •• ...n-^"^-^ 



Pacten scintillatusvar. corneoides, n. van, PI- 15- Figs. 15, 16. 



Pseudamusium claibornense Har., partim. Bull. Am. Pal., vol. 2, p. 



235, pl- i3> fig- I- 

 P. calvatus Dall (non M.ort) , partivi , Trans. Wag., Ill, 98, p. 752. 

 P. scintillatnsDaiW, parti m, id., p. 752. 



Specific characterization. — Form and size as indicated by the 

 figures (see also fig. in Bull. Am. Pal. referred to in the synony- 

 my) ; substance of the shell thicker when adult than in scintillat^ts 

 of the Jacksonian ; appearance like that of corneus of England, 

 though smaller ; surface practically without markings save the 

 fine concentric lines of growth and a few radiating rays on the 

 anterior ear, such rays when adult, separated by a rather broad, 

 smooth space from the anterior margin of the shell as indicated 

 in fig. 16 ; posterior ear in adult shell with exterior angle ap- 

 approximating 90° and not so obtuse as in scintillatus (fig. 14) 

 nor so acute as in calvatus ; j^oung shells in Mississippi, St. 

 Maurice stage, approaching close in outline to scintillatus, but 

 here as elsewhere so far as observed no Camptonectes marking 

 (so finely shown in scintillatus^ have been observed ; left valve 

 very flat in umbonal region, becoming deeper centrall}' and basal- 

 ly, with a faint, medial fold rapidly expanding basally. 



Type specimen. — The Hatchetigbee specimen figured in Bull. 

 Am. Pal, as cited above. 



Horizo7i. — Sabine and St. Maurice. 



Specimens figured. — Deposited in C. U. Mus., St. Maurice. 



Localities. — Three miles E. of Alto, Cherokee Co., near 

 Crockett, Houston Co., Tex. St. Maurice, Winnfield Marble 

 Quarry and Hammett's Branch, I^a. Hickory and Wantubbee, 

 Miss. Hatchetigbee, and base of bluff at Claiborne, Ala. 



Specimens of this form from Enterprise Miss., in the U.S. 

 Nat. Museum, No. 137,665, are labelled/*, scintillatus. 



Amussium squamulum Lamarck ? PI. 15. Figs. 17, 18. 



For synonymy and discussion see Bull. Am. Pal., vol. 2, p. 1897, p. 

 236. 



In the St. Maurice stage as exhibited about the mouth of 

 Negreet Ba5'^ou, I^a., there are often many badly preserved speci- 



