Revmn of Recent Geological Literature. 31S 
affirms that the Trinity division of the Comanche of Hill, is the equiv- 
alent of the upper, and perhaps of nearly all of the European Jurassic. 
These Trinity sands l)eing below the Tucumcari beds {i. c below the 
blue clay containing the Grijpluid <Ulnt(dii,\vcc. tucumcori Marcou), must 
belong to the Jura provided the Tucumcari beds belong there: and,^ 
per contra, the Tucumcari beds must fall into the Cretaceous if the 
Trinity sands belong there. Now Mr. Cummins refers his fossils to the 
"Tucumcari beds" as he has defined them, i. e. to some sandstones that 
are actually above the horizon of GrypJuea diUitata, var. turumcuri, and 
he parallelizes them with higher portions of the Comanche, viz., with 
the "Washita and Fredericksburg divisions. It seems quite likely that 
Mr. Cummins is correct in assigning those upper strata to the Cretaceous 
but the chief point of contention of Mr. Marcou, touching the under- 
lying strata, viz., Mr. Marcou's E, D, C, and B, or Mr. Cummins" Xos. 4 
and 5, seems not exactly disproved, and these may still remain in the 
Jurassic, at least until Mr. Cummins defines more closely in what por- 
tions of his Tucumcari beds he found his fossils. 
Mr. Cummins' report is a very valuable one, and bears strongly jyr///;*^ 
fiicie against the Jurassic in Pj'ramid mountain. 
Mr. Tail's report on the Cretaceous area north of the Colorado river 
agrees with that of Mr. Cummins in placing the Trinity sands in the 
Cretaceous, and he gives a diagram (p. 292) illustrating the unconform- 
able position of Bosque Cretaceous upon the paleozoic, with the "Trinity 
phase" at the bottom. The Trinity sands proper he shows are not an in- 
dividual entitj^ in the stratification, but are closely knit with the Glen Rose 
and Paluxy, these making a three-fold formation which he distinguisiies 
as the Bosque division. Overlying the Bos<][ue division are the Fred- 
ericksburg and tlie Washita divisions. It is a noteworthy distinction that 
3[r. Talf onlv finds the (xrypJid'n pilrhcri and the Exor/yrn texann, character- 
istic fossils of the Cretaceous, iu the upper divisions (p. 281). "The lowest 
limit of these fossils marks the upper limit of the Bos(iue division."' 
In the Bosque division is a different fauna, but few members of 
which extend into the higher divisions. In addition to the G-i-yphnn 
dildtatd, var. tucuiuctiri Marcou, which Mr, Cummins admits cannot be 
the same as the O. intcheri of the Cretaceous, and which is a fossil char- 
acteristic of the European Jurassic, ami the Ontvea ///''/'.vZ/i which Mr. ' 
C'ummins has not had opi)ortunity to compare Avitli European fossils of 
that name, both of which may be referred to the Bosque division. .Afr. 
Tail enumerates the following fossils from this division. 
1. In the Trinity sands; Trigonia, Ammonites, "Ostrea beds," (p. 2'J5); 
Ostrea franklini (pp. 297 and 310); Ostrea camelinis (Ms. of Cragin), 
pp. 303 and 307; Trunks of trees much silicitied, also clianged to lig- 
nite, constituting veritable driftwood, (p. 310). 
2. InWveGlen Rose member; Monopleura, Couiolina, Cuprotina (lu-- 
quienia) penguiuscula, Exogyra, Ostrea, Area. Ostrea subquadrata (pp. 
297-299): "Area and sniall Ammonites, allied to A. pedernales Jioemer,. 
and Nerinea occur abundantly in the marly line," /. ^;. in (Jlen Rose 
(p. 304): Ostrea camelinis Cragin (p. 307); (). franklini (p. .'.10): Cardium 
