268 CALIFORNIA ACADEMY OF SCIENCES. 



AGKAULOS. 



Ai-iotielliti^ owEXi Meek and Hayden; Pal. Upper Missouri, p. 9, figs, 

 a, b, c, pi. 1, fig. 4. Referred by VValcott, 1884, Pal. Eureka 

 Dist., Mou. U. S. Geol. Survey, vol. 8, p. 55, pi. 10, to Ply- 

 choparia oive.ni. 

 Arionellus (Bathyurics) planus Shum., 1861; Am. Jour. Sci., 2d 

 series, vol. 32, p. 219. Morgan's Creek, Burnet county, Texas. 



Taconic. 

 Ariojfllu'i PfSTULATUs Wal., 1877; Advanced sheets 31st Kep. New- 

 York State Mus. Nat. Hist., p. 15. Chazy, N. Y. 

 Arionellus pustulatus Wal., 1877; 31st Rep. New York State Mus. 



Nat. Hist., p. 68. 

 Arionellus quadrangclaris Whit., 1884; Bull. Mus. Nat. Hist, New 

 York, vol. 1, p. 147, pi. 14, fig. 8. Braintree, Mass. Taconic. 



QUADRAXGCLARis Wal., 1884; Bull. U. S. Geol. Survey, No. 10, p. 48, 



pi. 7, fig. 1. 



REDPATHi Wal., 1891; 10th Eep. U. S. Geol. Survey, p. 654, fig. 69. 



St. Simonds, Quebec. Taconic. 



soc'iALis Bill., 1874; Pal. Foss., vol. 2, p. 71 fig. 40. Chapel Arm., 



Trinity Bay, N. F. Taconic. 



sociALis Bill., 1882; Eep. of Progress Geol. Survey Newfoundland, 



p. 10, fig. 4. 



sociALis Matt., 1886; Trans. Royal Soc. Canada, vol. 2, p. 151, fig. 1 



a-b. 



sTRENurs Bill., 1874; Pal. Foss., vol. 2, p. 71, fig. 41. Topsail Head 



and Brigus, Conception Bay. Taconic. 

 STRENtJFS Bill., 1882; Re}), of Progress Geol. Survey of Newfound- 

 land, p. 10, fig. 5. 



sTREKUus Matt., 1886; Trans. Royal Soc. Canada, vol. 2, p. 153, figs. 



3, 3 a-b. 



STRENcrus Wal., 1891; 10th Rep. U. S. Survey, p. 655, pi. 96, figs. 1 a-c; 



also, var. nasulus, p. 654, pi. 97, figs. 2, 2 a-c. Olenellus zone. 

 Walcott refers Ptychoparia mucronatns S. & F. to this species. 

 Matthew uses the species for the type of the si;bgenus Strenuella, 

 Trans. Roy. Soc. Canada, 1886, p. 154. 



suhclavatus Bill. (See Ptychaspis subclavatus .) 



Arionellus (Bathyurus) texanps Shum., 1861; Am. Jour. Sci., 2d 

 series, vol. 32, p. 218. Clear Creek, Burnet County, Texas. 



Taconic. 



Arionellus tripuxctatus Whitf., 1876; Rep. Recon. Upper Missouri, 



p. 141, isl. 1, figs. 3-5. Moss Agate Springs near Camp Baker, 



Montana. Taconic. 



? wHiTEiELDiANus Matt., 1887; Trans. Roy. Soc. Canada, vol. 5, p. 130, 



pi. 1, figs. 1, 1 a-f. 



