OF CONCHOLOaT. 363 



River, Virginia; the Santee beds of South Carolina, &c. I 

 do not perceive from Mr. Gabb's Report, that there is any 

 mixture of Cretaceous and Eocene species in California, such 

 as we find at Wilmington, N. C, and in South Carolina. The 

 remarkable and very characteristic fossil, Radiolites gregaria, 

 abundant in California, has been omitted by Mr. Gabb in his 

 Report. The Older Eocene, which occurs in both Upper and 

 Lower California, is also found at Astoria, Oregon. 



Mr. Gabb makes two divisions of his Cretaceous strata, 

 A and B. The former is, doubtless, Cretaceous, and the latter, 

 I am sure, will prove to be Older Eocene. 



Fusus CaUfornicus, Gabb, pi. 28, fig. 205. I do not re- 

 cognize as my ? Clavatula Cali/ornica [Leihorinus CaUfornicus, 

 Con.) It does not come from the same locality as the latter, 

 and is striated and ribbed on the spire, in which characters 

 my species is wanting. 



Vohitilithes Navarroensis, pi. 19, fig. 56, belongs to my ge- 

 nus Rostellites, which is allied to FascioJaria, the colum- 

 ellar plaits being very oblique. It is probably identical with 

 R. Texana. The apparent dilatation of the labrum in the 

 specimen figured in the Mexican Boundary Survey, is owing 

 to its having been distorted by pressure. (Cretaceous.) 



Fusiis Remondii, pi. 18, fig. 36, is a species of Perissolax, 

 allied to P. penita, [Pyrula^) Conrad. (Eocene.) 



Perissolax hrevirostris is not a member of the genus, to 

 which it is somewhat doubtfully referred by Mr. Gabb. 



Naticina ohliqua, pi. 21, fig. 112, is an Eocene fossil. 



Amauropsis alveata is a species of Olohitlaria, Swainson, and 

 occurs, I think, in the Older Eocene limestone of South Caro- 

 lina, or a species very near to it. The genus is well repre- 

 sented in the Paris Eocene. Mr. Gabb evidentlj^ confounds 

 two species, as he remarks that the specimens in division B 

 (Eocene) are smooth, and those in division A (Cretaceous) are 

 striated. A comparison of his figures, pi. 19, fig. 9 (Eocene), 

 and pi. 21, fig. Ill, (Cretaceous), is sufficient to show a wide 

 specific difference. 



2'urritella uvasam, Con., pi. 21, fig. 92, is an Eocene species. 



Ficus mamillatus, pi. 32, fig. 276, is probably Sycotyptis 

 modestus, Conrad, an Eocene fossil from Oregon. 



Perissolax is a genus nearly related to Sycotypns, Browne, 

 and two other species should be referred to it, Fusus Hornii, 

 and Fusus Gooperii, Gabb, pi. 28, figs. 206, 207. The London 

 Clay of Bognor contains one species, Pyrula Smithii, Sow- 

 erby; the Paris Basin three species, Pyrula nexilis, elegans 

 and tricarinaia ; Claiborne, Ala., one species, Pyrula penita, 



