Weno and Pawpaw Formations 85 



ENGONOCERAS sp. 

 PI. 4, figs. 8-10 



The most numerous fossil in the basal Pawpaw clay is Engonoceras; 

 this genus is rare in the Duck Creek, Denton, Grayson, and Del Rio pyrite 

 faunae, and its abundance is diagnostic for the Pawpaw clay as so far 

 examined. There is probably more than one species in this formation. 

 The individuals are small (one inch or less), hematitic or pyritic, with 

 sharply etched sutures; flanks smooth and nearly flat; venter straight- 

 edged, angulated, concaved on the midline (so far as observed never acute 

 as in Metengonoceras) ; umbilicus narrow; sutures of varying complexity, 

 mainly very simple, with numerous auxiliary elements. 



HORIZON: Pawpaw formation, clay facies, abundant: Tarrant 

 County, numerous localities; Denton County, Johnson County. 



Grayson formation : marl facies and middle clay member, rare, Tarrant 

 and Denton counties. 



Denton clay : rare, Denison to Blue Mound, north of Fort Worth. 



Duck Creek marl: rare, Grayson to Tarrant counties. 



FLICKIA BOESEI n. sp. 



PI. 1, figs. 1-3 

 1920: Flickia sp. Winton and Adkins, Univ. Texas Bull. 1931, p. 69. 



HORIZON : Pawpaw formation, clay facies, base. 



LOCALITY : Type individual, base of Pawpaw formation, just or 

 top of Weno limestone escarpment, one-fourth mile east of Riovista-Waco 

 road and one mile south of Riovista, Texas. One eroded individual, the 

 type, was found here. 



MEASUREMENTS : Height of last whorl, 3.5 mm., width, 4.6 mm. ; 

 greatest diameter, 10.5 mm ; width of umbilicus, 3.7 mm. 



DESCRIPTION: Form discoidal, inflated, volutions thick, with thick, 

 crescentic section, moderately embracing, umbilicus deep, open, showing 

 at least five volutions. Cast smooth and unornamented. 



From the section of the end of the coil it is evident that the volution 

 at this age embraces only about half of the preceding one; the volutions 

 are also much broader and lower than in the adult Flickia simplex, having 

 at the end of the fifth (?) volution a ratio of breadth to height of 3:2. 

 The flank is broadly convex and passes into the umbilical wall by a sharp 



