GASTROPODA— STR0PH0STYLID2E. 



677 



222. H. textilis (Ulrich and Scofield). {Strophostylus textilis U. 



and S.) (Fig. 943.) Ordovicic. 



High-spired (apical angle 6o°-yo°), six or seven whorls ; re- 

 volving lines cancellated by oblique lines. 



Black River and Trenton of Minnesota ; Trenton of Kentucky. 



223. H. antiqua (Vanuxem). (Fig. 944.) Siluric. 



Fig. 944. Holopea antiqua, internal 

 molds. (Pal. N. Y., III.) 



Fig. 945. Holopea pervetusta, com- 

 plete shell and internal mold. (Pal. 

 N. Y.,III.) 



Siluric. 



High-spired, suture depressed, smooth except for lines of growth. 

 Manlius of New York, New Jersey, etc. Upper Monroe of 

 Michigan. 



224. H. pervetusta Hall. (Fig. 945.) 

 More slender and higher spired than 



preceding. Occurs with preceding. 



225. H. (?) proutana Hall. (Fig. 946.) 



Mississippic. 

 Very high-spired for the genus, apical 

 angle acute, aperture round-ovate, no um- 

 bilicus. FlG - 946. Holopea (?) 

 . proutana. (After Whitfield, 



St. Louis (Spergen) of Illinois and In- Am> Mus Nat< Hist< Bull>) 

 diana. 



LXXII 



FiG. 947. Strophostylus cyclosto 

 mus. (After Hall. ) 



Strophostylus Hall. 



Round-whorled shells, generally 

 with low spire and very ventricose 

 body whorl ; peristome round ; colu- 

 mellar lip twisted and grooved ; sur- 

 face often finely cancellated, though 

 frequently only lines of growth ap- 

 pear. Ordovicic-Carbonic. 



226. S. cyclostomus Hall. (Fig. 

 947.) Siluric. 



