932 = WV. T. Lupton—Meteoriec Iron from Coahuila. 
First, the invertebrate fauna of that formation is meager. 
Second, there is, as I believe, always an apparent conformity 
between the Dakota Group of the Cretaceous series and the 
Jurassic formation, wherever they have been found in contact. 
While I do not think that this conformity really proves that 
there is no hiatus between the two formations, I think the cir- 
cumstance of its existence more worthy of consideration than 
the assumed specific identification of the fossils which I have 
commented on. I regard these circumstances as at most only 
slightly opposing the evidence in favor of the Jurassic age of 
the strata in question which is afforded by its fossils, especially 
its vertebrate fauna. 
ese Jurassic strata are evidently not homotaxially related 
to the other North American strata which have by some authors 
been referred to the Jurassic. I refer to the Aucella-bearing 
rocks and their equivalents, which have been found in Call 
fornia, Washington Territory, British Columbia, Alaska, and 
the east coast of Greenland. Mr. Whiteaves follows Hichwald 
in referring these strata to the Neocomian; and I have sug- 
gested that they occupy a position upon the confines of the 
eocomian and Jurassic. These west coast and arctic beds 
appear to have no true equivalents in the United States to the 
eastward of the Pacific Coast region. 
PO 
Art. XXX.—Meteortc Iron from Coahuila, Mexico ; by 
N. T. Lupron. 
to my visit an expedition was sent out to bring in several 
a 
nd 
sent to the United States by Dr. Butcher, an American we 
was then living at Candela. The mass from which 1 succeed 
