243 LiGNiTic Stagk 51 



teriorly, but agrees well with the specimens in our colle(5lions. 

 Among the latter however, several specimens show a few high 

 concentric lines about the umbo. 



Fig 9 is a strangely elongated variety from Gregg's landing, it 

 presents no essential varietal features however, except its extreme 

 posterior prolongation. 



Localities. — Alabama : Butler ; Woods Bluff ; Nanafalia ; 

 Ozark. 



Type. — Aldrich's colledlion. 



Specimen figured. — Paleontological Museum, Cornell Uni- 

 versity. 



Leda corpulentoides, var's. PI. 8, figs. 10, 11. 



Syn. Yoldia corpulentoides Aid., Bull. Amer. Paleont., vol. i, p. 70, figs. 

 9, 9a., 1895. 



Aldrich' s original description. — Op. cit. p. 70. 



Mr. Aldrich very kindly sent us several duplicate specimens of 

 corpzdentoides from Tuscahoma, but they are all in a very imper- 

 fedl state of preservation. Our own collecftions contain the speci- 

 mens figured, presumably belonging to this species. Fig. 10 is 

 from Gregg's landing, is quite tumid centrally and is almost de- 

 void of surface sculpture except traces of fine concentric lines. 

 It is, however, accompanied by younger forms showing stronger 

 concentric lines centrally, which diminish in strength anteriorly 

 and which when arriving at about the longitude of the posterior 

 channel in Fig. 1 1 , suddenly terminate in a slightly enlarged 

 granule ; this feature is clearly noticeable near the beaks only. 

 The corpulentoides from Tuscahoma are all adults, and are some- 

 what stouter than the Gregg's landing specimens, but it seems 

 probable that all will eventually prove to be identical. 



Fig. 1 1 is from Nanafalia and agrees fairly well with corpulent- 

 oides, except the channel just anterior to the umbonal slope is 

 very deep, the concentric lines are coarser, and the general form 

 of the shell is somewhat less inflated than elongatoides. 



Type. — Aldrich's colledlion. 



Specimens figured. — Paleontological Museum, Cornell Uni- 

 versity. 



Leda marieana. PI. 8, fig. 12. 



Syn. L. marieana Aid., Bull. Amer. Paleont., vol. ii, p. 182, pi. 6, fig. 5. 



