THE RECENT AND FOSSIL MOLLUSKS OF THE GENUS 

 CERITHIOPSIS FROM THE WEST COAST OF AMERICA. 



By Paul Bartsch, 



Assistant Curator, Division of Mollusks, U. S. National Museum. 



The first Cerithiopsis known from the west coast of America was 

 reported by Alcide D'Orbigny in 1840 from Peru. 1 This was fol- 

 lowed twelve years later by two additional species, discovered by 

 Prof. C. B. Adams at Panama and described as Cerithium neglectum 

 C. B. Adams and Triforis infrequens C. B. Adams. 2 



In 1857 Dr. P. P. Carpenter published that part of his Catalogue 

 of Mazatlan Shells which deals with the members of this genus, citing 

 the following species: 



tuberculides Carpenter. sorex Carpenter. 



tuberculoid.es albonodosa Carpenter. convexa Carpenter. 



cerea Carpenter. decussata Carpenter. 



pupiformis Carpenter. assimilata C. B. Adams. 



Of these, C. convexa is now placed in the genus Metaxia. C. decussata 

 is a Bittium, and Cerithiopsis assimilata Carpenter = Cerithium 

 assimilatum C. B. Adams must be referred to the genus Seila. 



In 1865 Doctor Carpenter described Cerithiopsis intercalaria 3 and 

 at the same time referred Cerithium bimarginatum C. B. Adams to this 

 genus. At present both of these species are placed in the genus 

 Eumeta. In the Supplementary Report on the Present State of Our 

 Knowledge with Regard to the Mollusca of the West Coast of America 4 

 Doctor Carpenter published a terse diagnosis of the following species: 



Cerithiopsis columna. Cerithiopsis purpurea. 



Cerithiopsis munita. Cerithiopsis fortior. 



All of these were later more fully described. Three of them, 

 C. munita, C. purpurea, and C. fortior, are now placed in the genus 

 Bittium. In 1867 De Folin added another species, 5 Cerithium 

 destrugesi, which may not belong to our fauna, as the locality is cited 

 as Panama or Negritos Island. 



i Voy. Amer. Merid., p. 443, pi. 77, figs. 9-10. 



* Ann. Lye. Nat. Hist, of N. Y., 1852, pp. 379-80. 

 a Proc. Zool. Soc, 1865, p. 281. 



* Rep. Brit. Ass. Adv. Sci. for 1863, published in 18C4. 

 « Les Meleagrinicoles, p. 71, pi. 6, fig. 12. 



Proceedings U. S. National Museum, Vol. 40— No. 1823. 



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