286 HENRY SHALER WILLIAMS 
the New York Chemung, it will promote the main investigation, 
in which I am as thoroughly interested as Mr. Weller can be, to 
have the fact clearly expressed at the outset. 
The belief in the dual origin of the Chouteau fauna is drawn 
by Mr. Weller from an analysis of the fauna itself. I have 
examined the lists and the argument for new evidence bearing 
upon the general problem of the movement and modification of 
the fossil faunas concerned, but the evidence appears to me con- 
clusive in proving a single and direct origin from the one gen- 
eral European type of Devonian represented already in the 
Devonian faunas of Iowa and other regions of the north and 
west. 
Critical examination of the genera listed as belonging to the 
‘‘Fast-American Devonian Province,” but wanting in the ‘‘ West- 
American and European Devonian Province”’ does not confirm 
the opinion of an origin for any of the genera directly from the 
former eastern province. 
The genera so listed are Aviculopecten, Cardiopsis, Edmondia, 
Pterinea, Sphenotus, Straparollus, Genneéocrinus, Platycrinus, Scaphio- 
crinus, Michelinia. 
Regarding them the following comments may be made: 
Aviculopecten is reported in numerous species as European 
Devonian by Frech* and Tscherneyschew.? 
Cardiopsis is a form of such uncertain generic affinities that 
the absence of the genus should not be concluded from the 
absence of the name in lists of foreign faunas. The close rela- 
tionship of the one species, recognized by this generic name 
from America by Hall, to Cardiomorpha, Megambonia, Dextobia 
and Dualina is sufficient to prevent it from furnishing any 
positive evidence of origin outside of the typical European 
Devonian. 
tFRECH, Die Devonischen Aviculiden Deutschland, K. Preuss, Geol. Lands, 
Abhandl. 
2 TSCHERNEYSCHEW, Special Karte v Preuss, a Thiiring, Staaten, Bd. IX. bft. 3, 
1891. 
Die Fauna des unteren Devon am Ostabhunge des Ural. Mem. du Comité Geol., 
Vol. 1V., No. 3, 1893. 
