228 0. A. White—JSurassic Strata of North America. 
ArT. XXIX.—WNotes on the Jurassic Strata of North Ameria ; 
by CHarLEs A. WHITE. 
It is in the lower division only, so far as I am aware, that 
any invertebrate fossils have been found: and it is upon these 
that was based the earliest published opinion as to the Jurassi¢ 
This fauna has been brought out mainly by Professor Marsh, 
who has published the results of his investigations in this a 
nal from time to time during the past eight years. It is mal) ‘4 
reptilian, but it also embraces many mammalian forms. ee 
fessor Marsh refers all this remarkable fauna unhesitating’y 
to the Jurassic period, and all paleontologists agree wit! him 
in this respect. Let it be remembered that a part of this ve 
tebrate fauna is associated in the same layers with the ine 
-brate fauna which has been referred to, and a part of it com’ 
from layers which overlie them. | 
