ENGONOCERATID i. Head 
dwarfed form of this species, since in the earlier parts of same volution the 
sutures are well separated, as in other forms. 
The ventral lobes are obliterated, but sufficient of the first lateral 
saddles remain to show that they were equally bifid and that the outer arm 
was also bifid the inner arm entire and quite large. The second to fourth 
saddles were, on the left side, broad and entire, the fifth to seventh 
symmetrically and deeply bifid. 
Locality: Near Austin and Benbrook, Tex. 
Age: Fredericksburg group, Comanche series. 
ENGONOCERAS EMARGINATUM (Cragin)." 
Sphenodiscus emarginatus Cragin, 1893, Geol. Sury. Texas, Fourth Ann. Rept., p. 245. 
According to Cragin’s description, this species has the concave venter 
until a late stage, but has the tubercles and sutures of this genus. 
EINGONOCERAS ROEMERI (Cragin). 
Sphenodiscus roemeri Cragin, 1893, Geol. Sury. Texas, Fourth Ann. Rept., pl. 46, 
fig. 1. 
Cragin describes this shell as having ‘‘venter narrowly truncate, the 
ventro-lateral angle at first sharp, becoming on the body-chamber subtu- 
berculate-sinuous.” This and the general outlines of the sutures, if they are 
supposed to be deprived of their marginal saddles, as they must have been 
in the young of this shell before these were developed, has caused me to 
refer the species provisionally to this genus The sutures are, however, 
obviously more complex as figured by Cragin than in any other known 
form of Engonoceras. The principal saddles are all bifid, trifid, or quadrifid, 
and the smaller saddles inside of what appears to be the fourth saddles are 
mostly bifid. 
Mr. Stanton has written as follows regarding this form: 
According to Cragin, this is from the ‘‘alternating beds”—that is, the Trinity 
division—not Fredericksburg, as given in your MS. If this be true (and Mr. Taft’s 
stratigraphic data look all right), the form is probably the oldest one of this group 
that we have from the Comanche series. 
Locality: Iredell, Bosque County, Tex. 
Age: Comanche series, Glenrose beds. 
“See p. 157, where this species is doubtfully referred to Protengonoceras.—T. W. S. 
MON XLIV-—03: 12 
