314 The American Geologist. November, 1802 
mediale, Natica, Cyrena, Goniolina (p. 813); Anomia (p. 815); Turritella, 
Cardium mediale and C. hillanum, Pleurocera, Serpula, Trigonia crenu- 
lata (pp. 0I6, 817); Cardium mediale (p. 337). 
3. In the Pidu.ry member; no fossils are named from the Paluxj-. 
These Trinity fossils can none of them be pronounced Cretaceous by 
reference to any undoubted standard of comparison. The genus Tri- 
gonia ranges from the Lias to the Chalk, Amuionites from the Oi.llte to 
the present. Ostrea franklini was placed in the Cretaceous by Coquand 
without any authority whatever, except a surmise by Mr. Marcou that it 
was obtMined "somewhere near the locality of Gryphsva pitcheri." It 
was published in the Arkansas geological report of Owen by Mr. E. T. 
Cox, without any description, only the illustrated plates having been 
found after Owen's death."* Ostrea camelinis, of the manuscripts of 
Prof. Cragin, being a new species has no authority as a guide to the age 
of the strata containing it. 
In the Glen Rose member, which by Prof. Hill was not associated with 
the Trinity but was retained in the Fredericksburg division, the reported 
species are more affiliated with the Cretaceous, but there is not yet 
sufficient volume of a distinctively Cretaceous fauna to carry its assign- 
ment to that age beyond the limit of doubt. A large fauna is given the 
Fredericksburg division bj' Prof. Hill, but it is uncertain what part of 
it belongs in the (Jlen Rose division, detached from the Fredericksburg 
by Mr. Taff and placed in the Bosque division, but it appears to be but a 
meager portion of it — probably that which Mr, Hill has embraced in his 
"basal beds" of the Fredericksburg division. However, Mr. Taff mentions: 
Monopleura, may be either in the " basal beds "' or the Caprina lime- 
stone of Hill. 
Goniolimi, in magnesian limestone, with bivalves and gasteropods. 
Caprotina (Requunic) penguiuseuht, apparently a fossil of the " lower 
beds" and of the Caprina limestone. The genus is found in the upper 
Greensand of France. 
Exogi/VK, in the basal, alternating beds. The genus also is found much 
higlier, as well as in the .1 urasbic. 
Ostrea, ranges from the Jurassic upward. 
Area, ranges from tlie Trinity sands to the Washita division. 
" Ostrea suhguadrata." Thin bedded limestone. Not mentioned by Hill. 
Ammonites. Ranges from the Lias to the Chalk. Hill gives A. peder- 
nalis Von Buch, in the Comanche Peak chalk. 
Nerineii, is a .Jurassic genus. 
Ostrea (•(imeHnis ms. of Cragin. From the Triuity to the Glen Rose. 
OslreafranAiini Coq. is abundant in the Trinity. 
Cardhun mediale. Is given hy Hill only for the Comanche Peak lime- 
stone, which is next above the " lower beds," but Mr. Taff found it im- 
mediately above the Trinitj^ sands, and therefore at the base of the al- 
ternating or "basal beds." 
2\'atica. Ranges from the Devonian to the present time. 
Gyrena. A fossil of the Wealden, ranging upward. 
*riiis is on tlie statcinent of Mr. Marcon, American Geoi-ogist, vol. iv, )>. 3.56, 188!t. 
