THE RECENT AND FOSSIL MOLLUSKS OF THE GENUS 

 BITTIUM FROM THE WEST COAST OF AMERICA. 



By Paul Bartsch, 



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



The first Bittium known from the west coast of America was 

 reported by A. A. Gould Y in 1849, when he described Cerithium 

 Mosum from the northwestern coast. Unfortunately, Philippi had 

 used this name for a different species the year previous, thus pre- 

 occupying the above combination. The same year A. T. von Midden- 

 dorff 2 described the same species as Turritella eschrichtii. 



Bittium eschricJiti Middendorff remained the unique representative 

 until 1857, when Dr. P. P. Carpenter 3 published Cerithiopsis decus- 

 sata from Mazatlan, Mexico. To these William M. Gabb 4 added 

 Turbonilla aspera, a fossil species from the Lower Pleistocene of 

 Santa Barbara, California, in 1861. Bittium nitens, a fourth species, 

 was described by Doctor Carpenter 5 in 1864, from Cape St. Lucas, 

 Lower California. 



A large number of new forms were listed in the Supplementary 

 Report on the Present State of our Knowledge with Regard to the 

 Mollusca of the West Coast of North America, by Dr. P. P. Car- 

 penter 6 in 1864. In this report Doctor Carpenter gives a list of the 

 shells known to him and adds a few words of diagnosis to the new 

 forms, which are later fully described in various journals. The 

 species here listed are: 

 Cerithiopsis munita, pages 628 and Bittium ? var. esuriens, page 655. 



660. Bittium attenuatum, page 655. 



Bittium Jilosum Gould = Es c h- 



richtii Middendorff, page 655. 



i Proc. Bost. Soe. Nat. Hist., vol. 8, p. 120. 



2Beitr. Mai. Ross., vol. 2, 1849, p. 68, pi. 11, fig. 1. 



a Cat. Mazatlan Shells, 1857, p. 308. 



« Proc. Acad. Nat. Sci. Philadelphia, p. 308. 



6 Ann. Mag. Nat. Hist., ser. 3, vol. 13, p. 479. 



« Rep. Brit. Ass. Adv. Sci. for 1803, published in 1864. 



Proceedings U. S. National Museum, Vol. 40— No. 1 826. 



383 



