360 TRANSACTIONS OF THE WAGNER FREE 



Florida coast south to the x-\ntilles, Brazil, Ascension Island, and in the Pacific 

 from California to Peru. 



A single specimen in perfect condition was found in the marls. 



An imperfect cast of an Amalthea, resembling A. Willcoxii, but with less 

 prominent radiating sculpture, was found by the writer in the " white lime- 

 stone," or Jacksonian, from the bluff at Claiborne, Alabama. A curious fos- 

 sil has been described from the Costa Rica Pliocene, under the name of 

 Hipponyx crepidula, by Gabb. It is certainly not a mollusk, and has some- 

 what the aspect of one of the shelly appendages of a cirrhipede like Scalpel- 

 luni. Several species of Amalthea, common to the recent fauna, are found in 

 the Pliocene and later beds of the Californian coast. 



Family XENOPHORID.F:. 



" Genus XBNOPHORA Fischer. 



Xenophora conchyliophora Born. 



Plate 4, figures 10, 10 a. 



Trochus conchyliophorus Born, Mus. Cass. Ind., p. 333, 1778. 



Xenophora laevigata G. Fischer, Tabl. Syn. Zoogn., p. 113, 1808. 



? Trochus leprosus Morton, Syn. Org. Rem., p. 46, pi. 15, fig. 6, 1834. 



Phorus reclusus Conr., Proc. Acad. Nat. Sci. vii. p. 262, 1855 ; Wailes, Geol. Rep. Miss., 



p. 289, pi. 17, figs. 5 a, 6 b, 1S54. 

 Onusius rechiszis Conr., Am. Journ. Conch, i. p. 33, 1865. 

 Xenophora humilis Dall, Part i. p. 182, pi. 4, figs. 10, 10 a ; not of Conrad. 

 Xenophora agglutinans (Lam.) De Gregorio, Mon. Eoc. Ala., p. 144, 1890. 

 Xenophora reclusa De Gregorio, op. cit. p. 144. 



Uppermost Cretaceous (Ripley) of Alabama, at Prairie Bluff, Ala., Morton 

 and Conrad, and of Crosswicks, N. J., Whitfield ; Eocene of Wood's Bluff, 

 Ala., Aldrich ; of Jackson, Miss., Wailes and Conrad; Older Miocene of the 

 Chipola group, in the Orthaulax bed at Ballast Point, Tampa Bay, Florida, 

 Willcox ; and of the Tampa limestone at Bartow, Fla., Eldridge ; Newer Mio- 

 cene of Cape Fear River at Mrs. Purdy's marl-bed, Johnson ; Pliocene of the 

 Caloosahatchie and Shell Creek, Fla., Dall and Willcox ; living in moderate 

 depths of water off the eastern coast of the United States from Cape Hatteras 

 southward to the Antilles and in the Gulf of Mexico, U. S. Fish Commission. 



Since this group remounts in the geological scale to the Devonian, it is 

 not so extraordinary that one of the species should persist from the uppermost 

 Cretaceous to the present day. No differential characters have ever been re- 

 corded which would separate Morton's shell from the Eocene form which fol- 

 lows it, and I can assert with confidence that the latter cannot be discriminated 

 from the Miocene and recent forms by any constant characters. If this suc- 

 cession be admitted, it is a strong testimony to the protective value of the de- 

 vice by which the members of this family defend themselves. 



The specimen figured in Part I. was hastily identified as X. Jmniilis from a 

 specimen so named in the collection, but on examination later I found the 



