IOWA ACADEMY OP SCIENCE 
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Valley and> Sierra limestones. The Lake Valley limestone, carrying the typical 
fauna of the- Lower Burlington limestone was originally fully described by 
Springer.! . Its northward extension to the Magdalena range, 100 miles away,, 
was recently noted. § Herrick’s title** “Graphic-Kelly lime,” for a part of this 
formation, that has crept into geologic literature during the past year, was not 
intended to have exact geologic definition but merely local mining significance, 
referring, to mines of that name. . The Grande limestone appears to. contain the, 
fauna of the Chouteau limestone of. Missouri. The Sierra limestone is a for- 
mation higher than a.ny other of the Early Carbonic strata yet recognized in 
the Southwest. Gordon is mistaken in regarding all three of these divisions 
as the original Lake Valley limestone. 
The only known Carbonic- coal-bearing formation in the Southwest is included, 
in the Ladronesian series. It is thought to be an extension or representative 
of the Arkansan series of the southern Ozark region. Being sharply delimited 
above and below by marked unconformity planes of erosional character 
it was doubtless once one of the most important formations of the region. Her- 
rick,* *, who first noted the beds, though not recognizing their true significance,, 
referred them to the Upper Carbonic, but he subsequently was convinced that 
they w^ere of earlier age. The series will doubtless be found to be wide-spread 
though possibly only in remnantal areas. t No one who has seen the two for- 
mations w^ould think of correlating the beds of this series with any part of 
the Sandia shales. Its fauna and flora ia a theme of great interest as it must 
be so unlike anything else in the West. 
It is a matter of great surprise that the recent considerations of the beds 
constituting the Manzanan series should give rise to such a confusion of ideas 
as they have. It can only be accounted for by the cursory and incomplete 
character of the examinations during hasty reconnaisance work which has 
been the usual method in the region. The use of the term Mamzanan is an, 
attempt to preserve Herrick’s title without introducing new names. To be 
sure, it was not at first definitely delimited, but since no other title for the 
beds in question has intervened there appears no good reason for abandoning 
the term, or for using it for a very different section having no elements in 
common with the first one. 
As he himself has often in person explained, Professor Herrick in none of his 
published writings ever intended to formally propose any of the geolographic 
names wdiich he used provisionally. The formal proposals of the necessary 
geologic titles and their definition was reserved for a special memoir which I 
believe v/as well along towards completion at the time of his sad demise. The 
intentionally informal character of the few geographic names he use . from time, 
to time is clearly indicated in all of his v/ritings. His term Manzano, for ex- 
ample, is used in a number of different senses in as many different places; 
one referring to the gray limestones between the red-beds and the red quart- 
zite at the top of his Sandia shales. The title Bernalillo shales, which I had 
suggested for the Mid-Carbonic red-beds, was acceptable to him and would 
have been used by him in his final memoir. 
lAm. Jour. Sci. (3), Vol. XXVII, p. 102, 1884. 
§Proc. Iowa Acad. Sci., Vol. XII, pp. 169-171. 1905. 
** American Geologist, Vol. XXXII, p. 311, 1904. 
*Journal of Geology, Vol. XII, p. 242, 1904. 
tEng. & Min. Jour., Vol. LXXXI, p. 1129, 1906. 
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