'4l8 TRANSACTIONS OF THE WAGNER FREE 



Tiburnus De Gregorio, Faun. Eocen. Alabama, p. 143, 1890 ; subgenus of Turbo, type 7". 



naticoides Lea. 

 Turbo sp. Lea ; Natica sp. Conrad. 



Dill-wrynella naticoides Lea. 

 Plate 18, figure 3. 



Natica eborea " Conrad," Foss. Sh. Tert. Form., No. 4, p. 46, Oct., 1833 ; Cat. Tert. Sh. 



U. S. in Morton's Synopsis Org. Rem. Cret., App., p. 4, 1S34; Orb., Prodr. Pal. ii. p. 346, 



No. 137, 1850. 

 Turbo naticoides Lea, Contr. Geol., p. 125, pi. iv. fig. 114, Dec , 1833. 

 Monilea eborea Conr. (MS. label), in S. L Coll., not of Wagner. 

 Turbo {Tiburnus) naticoides De Greg., op. cit. p. 143, pi. 13, figs. 21 to 26, 1890. 



Claiborne sands horizon of the Eocene at Claiborne, Alabama. 



Shell small, turbinate, solid, polished, smooth, not pearly, of four or five 

 whorls ; suture distinct, not channelled ; upper surface and periphery rounded ; 

 nucleus minute; sculpture only of faint incremental lines; base rounded, 

 minutely perforate or with a deep, narrow pit in the umbilical region ; pillar 

 broad, slightly callous, with a faint groove behind it, passing insensibly into 

 the lower lip ; aperture oblique, lip not reflected ; throat smooth. Alt. 6 ; 

 max. diam. 7 mm. 



Natica eborea, published by Say and Morton in Conrad's name, was not 

 figured or recognizably described. Conrad himself afterward blundered in 

 trying to identify it. The name of Lea, which was accompanied by a good 

 figure, is therefore adopted here. 



Owing to the similarity of the specific names and the circumstances above 

 mentioned, Conrad seems to have confounded this species with Wagner's 

 Troclms eborcus, which it does not resemble. It differs from the recent type 

 of Dillwynella by its larger size, more elevated and compact form, but other- 

 wise is extremely similar to it. There is a faint dimple of callus on the pillar 

 in both, but it is more prominent in the recent species. None of the specimens 

 show any trace of nacre, thereby agreeing with the porceJlanous character of 

 the recent Dillwynella. The only shell with which this is likely to be con- 

 founded is the Calliostoma nitens Lea, which is smaller, more depressed, more 

 angulated at the periphery, and provided with a thick and very brilliant 

 nacreous layer, which shines through the thin outer stratum of the shell in 

 many specimens. 



Genus OOOHLIOLBPIS Stimpson. 

 CocktiotepisSlm., Proc. Bost. Soc. Nat. Hist. vi. p. 308, 1858. 



The systematic position of this genus is not yet absolutely certain. The 

 type is the following species : 



Cochliolepis parasitica Stimpson. 



C parasitica Stm., Proc. Bost. Soc. Nat. Hist. vi. p. 308 (fig'd), 1S5S ; Dall, Rep. Blake 

 Gastr. , p. 360, 18S9. 



