I I -IH-IKA 8ULOATA, . Sp. (Ulrich.) 

 PLATl I \\\. K108.-T. 



Shell subfuKlfnrni. consisting of about six. gradually Increasing and very depressed-convex whorls, 



ihe last one of which forms about two-fifths of the entire length <>f the shell; apical angle about S2; 



deep In casU, scarcely distinguishable externally, the shell beln thick; aperture elongate, 



i.tiii.|uely Hubelllptleal, strongly modlfled above by the preceding whorl, somewhat acuminate at both 



l; surface of cast with several more or less obscure revolving furrows; exterior of shell appearing per- 



fectly smooth and glossy to the naked eye, but under a good glass showing revolving rows of very minute 



puncUe, as shown In OR. 7. 



The whorls are less convex In the spin-, the last Is more abruptly contracted below, and the test only 

 about half as thick as In F. chuthtrd. The revolving furrows shown on the Interior cast distinguish It 

 from all previously described species of the genus. 



Formation and locaWry. From the base of the Utlca group or top of the Trenton, at Roger's gap, 

 iitucky. 



OoUeefion.-K. O. Dlrlch. 



IVsiSI'IRA 8UBF08IFORMI8 Hall. 

 PLATE LXXXI. K108. M and W. 



JfrnAwoiMa mbfutifnrmu HALL, 1847, Pal i. I. p. 180; also 1860, Third Rep. N. Y. St. Cab. 



Nat I! ' i' 171, pi. IV. fig. 2. 



Fumtpira wVunformfc HALL, 1871, Twenty -fourth Rep. N. Y. St. Cab. Nat. Hist, p. tt. 

 itAfuttformit 8. A. MILLKK, 1874, Cln. Quar. Jour. Scl., vol. I, p. 316. 



CasU of the Interior elongate-subfuslform, the spire elevated, ascending with moderate rapidity, the 

 apical angle 25 or 28; volutions six or more, casts, however, rarely retaining more than four, very moder- 

 ately convex and generally about a third wider than high In the spire; last whorl contracting rapidly 

 below; aperture somewhat semi-elliptical, the length equalling about two and one-half times the greatest 

 width, and only a little more than one-third of the total length of the shell; outer Up curving forward 

 slightly In the middle; suture of very moderate depth In casts, from which we assume that the test 

 was thin. 



Hall's original figures In his 1847 work give, as he states himself In the museum report cited, " but 

 a very Imperfect Idea of the species." Furthermore, we are satisfied that his original figure* Include more 

 than one species, the apical angle and form of the aperture being quite different In figs. 2a and 2c, pi. 



: X. In Identifying the species we have relied chiefly upon Hall's figure of a better specimen In the 

 third museum report. The species is reported from the Utlca group at Cincinnati, but we are Inclined 

 to doubt that the form found there Is strictly Identical with the Trenton originals of the species. 



F. tubfuriformi* is one of several closely related species. Of these F. tertbriformit Hall, from the 

 Utlca group at Cincinnati, has a shorter spire, relatively longer aperture, and more convex whorls. 



Formalin* and (oeatity. Rare In the Fuslsplra bed of the Trenton group, In Goodhue and Flllmore 

 counties, Minnesota. Also In tin- middle pinion of th-- k'rup near Burgln, Kentucky. The species Is 

 frequently quoted In lists of Trenton fossils In New York and Canada, but as far as our experience Is con- 



I. It appears that several species are there confused under the one name gubfutiformit, among them 

 the next described F. ooneexo. 



CWbetfM. K. O. Ulrkh 



FUSISPIRA rONVKXA. M. Sp. 



PI.VTI 



Thlsshell resemble* F. nbftotformii Hall but differs In the following particulars: The apical angle Is 

 wider, belug from 39 U> 37. the latter In the specimen regarded as the type of the species; the whorls are 



