674 REVIEWS 
Tarr’s statement that a thousand feet or so of rocks come in over the white 
limestone (Capitan) a little farther north in New Mexico, would seem to be 
indicative of the stratigraphic position of the Guadalupe beds. However, 
the age of the uppermost beds has not been ascertained. Even though they 
were Triassic it would seem to leave the Guadalupe beds below the Permo- 
Triassic unconformity which is known to exist in the Texas Panhandle, 
northern New Mexico, and Colorado. This would leave a strong possibility 
of the Capitan limestone being no younger than the Whitehorse beds, or 
the Quartermaster beds' at best. | 
However, Dr. Girty, who has been over the south end of the Guadalupes 
passes Tarr’s statement —that ‘‘the total section exposed in the Guadalupes, 
approximately stated, cannot be less than 4,o00 feet, including the New 
Mexico series, which exist above the white limestone’’—with the remark: 
I do not know what rocks are intended by this indefinite statement. The 
Capitan limestone is not known in Texas, so far as I am aware, save in the Guada- 
lupe Mountains and the foothills adjacent, where no overlying series is exposed. 
It must of necessity extend northward into New Mexico, unless faulted out, but 
all our faunas from New Mexico, so far as I have examined them, show an alto- 
gether different facies, one more suggestive of beds which there is every reason to 
believe lie below the Guadalupian. 
The fauna consists of 326 forms: Protozoa, 9; Sponges, 24; Coelenter- 
ates, 10; Echinoderms, 7; Vermes, 1; Bryozoa, 44; Brachiopods, 128; 
Pelecypods, 45; Scaphopods, 1; Amphineura, 1; Gastropods, 42; Cepha- 
lopods, 9; Crustaceans, 5. ‘‘Aside from the species which Shumard had 
described, most of the Guadalupian forms appeared to be new.” The 
characteristics of the various classes are briefly mentioned, followed by lists 
from the various localities and horizons. 
The principles which have guided the author in making his determina- 
tions are stated as follows: 
It has been said no less truly than often that it is easier to combine two species 
that have been injudiciously discriminated than to disengage two species that have 
been injudiciously combined, and it is also true that loose discriminations and 
loose identifications lead to loose correlations. I have felt under obligations to the 
workers in this field to leave a species whose relationship I was unable to deter- 
mine as unentangled as possible, and to establish the nomenclature on a reason- 
able and permanent basis. Consequently, in doubtful cases I have leaned con- 
sciously to the side of species-making, nor would I feel deeply concerned should 
it prove on just evidence not now accessible to me that some of my names are 
synonyms. 
1 See Kans. Univ. Sci. Bull.; IV, No. 3, pp. 115-71, 1907. 
