232 PROCEEDINGS OF THE ACADEMY OF [1888. 



This species is represented by two specimens, one of which is 

 somewhat crushed. There appears to be satisfactory evidence that 

 Marcou's name has priority. Dr. White says in a foot note on p. 

 125, volume IV, of Explorations and Surveys west of the 100th 

 meridian : 



" Orthis pecosi, Retzia mormoni, Mhynchonella iita, li. rocJcpnon- 

 tana, and Spirifer rockyinontana were jiublished by Marcou in his 

 Geology of North America. I have obtained satisfactory evidence 

 that the work was published as early as March 1, 1858. Vol. XV, 

 of the Bulletin de la Societe Geologique de France contains a 

 statement that a copy of the book was sent to that society on April 

 20, 1858. In the same year Shumard and Swallow published a 

 paper containing descriptions of the three first named species, under 

 other names, in the transactions of the St. Louis Academy of Sci- 

 ences, but that publication was not made until about the first of 

 June. In December of the same year, Hall published in the 

 Geological Report of Iowa, Spirifer a rockymontana as S. opimus; and 

 in 1860, McChesney published R. rockymontana as R. etoniaformis. 

 It thus appears clear that Marcou is entitled to priority of all five 

 of the names given above, as stated in the synonymy heading the 

 descriptions of those s^iecies in this report," 



LAMELLIBRANCHIATA. 



Myalina swallovi McChesney. 



Myalina swallovi McChesney, 1860. New. False. Foss., p. 57. 



Myalina swallovi Meek and Worthen, 1866. Geol. 111., II, p. 

 341. 



Giant mine : not common ; some, of those obtained are in an ex- 

 cellent state of preservation. 



Aviculopecten coxanus Meek and Worthen. 



Aviculopeden coxanus Meek and Worthen, 1860. Proc. Acad. 



Nat. Sci. Phila., p. 453. 

 Aviculopecten coxanus Meek and Worthen, 1866. Geology 111., 



vol. II, p. 326. 

 Of this little species six good specimens have been obtained at 

 the Pioneer mine ; none of them are larger than that figured by 

 Meek and Worthen (loc. cit). 



Aviculopecten negleotus Geinitz. 



^ Pecten neglectus Geinitz, 1866. Carb. und Dyas in Net)raska, p, 

 33. 



