ENGONOCERATID®. 185 
there are strong indications that the venter became acute in an early 
ephebic substage. 
The matrix of these specimens is a red, apparently calcareous, clay 
stone, and indicates a distinct formation from that containing the species of 
Placenticeras cited from the same locality and also in the Boll colleetion in 
the Museum of Comparative Zoology. They have remnants of the 
nacreous layer and one has the shell still left in the umbilicus. The 
interior is so much crushed together that it is impossible to say that the 
venter was or was not concave in the internal volutions. Certainly, so far 
as the cast goes, the outer volution was unquestionably subacute. 
Three fragments in Cragin’s collection from the Grayson marl, one- 
half to three-fourths mile southeast of the Union Station, at Denison, Tex., 
have the phylloidal saddles and long complex lobes of this species and also 
subacute venters. The last volution of one of these fragments reaches 
ventro-dorsal diameter of 60 mm. while still septate, and has a transverse 
diameter of 24 mm. The sutures, however, are too much abraded for 
efficient observation. 
The peculiar first lateral saddles of this species, the extremely phylli- 
form saddles, narrow lobes with spreading and digitate extremities, and 
straightened sutures, separate this from M. inscriptwn. The larger size of 
the lobes and saddles enables one, as well as the more persistent acuteness 
of the venter in the gerontic stage, to distinguish it from M. dwmbli. 
Mr. Stanton has written as follows with reference to this fossil: “TI 
think this is certainly from the Upper Cretaceous and probably from the 
Eagle Ford shales, like the other specimens with the same locality label. 
Such brownish-red concretions are common in weathered portions of the 
Eagle Ford shales.” 
Locality: Elm Fork and West Fork (Horton’s mill), Dallas County, 
Tex. 
Age: Probably Eagle Ford shales, Colorado group, Upper Cretaceous. 
METENGONOCERAS DUMBLI (Cragin. ) 
Pl. X XVII, figs. 3-14. 
Sphenodiscus dumbli Cragin (pars), 1893, Geol. Surv. Texas, Fourth Ann. Rept., 
p- 243, pl. 44. 
A superb specimen in collection United States Geological Survey, 
diameter 94 mm., although in three pieces and with nepionic stage and part 
