16 ARCHIVOS DO MUSEU NACIONAL 
ceiro, ainda que algumas tenham as- 
pecto jurassico, nenhuma póde ser iden- 
tificada com qualquer especie jurassica 
conhecida. Finalmente, como todas as 
colleeções mostraram pertencer a uma 
fauna, e como uma parte das especies é 
incontestavelmente da edade cretacea, 
toda a fauna deve necessariamente ser 
referida a esse periodo. 
Os fosseis descriptos nestas memorias 
representam uma fauna que oferece 
certas differenças notaveis de qualquer 
das faunas cretaceas descobertas em ou- 
tras partes do mundo. Além disso, quanto 
a seus typos molluscos, esta fauna brazi- 
leira parece ter relações mais intimas 
com a fauna cretacea da India Meridional 
do que com qualquer outra até hoje estu- 
dada. A fauna immediatamente seme- 
lhante é talvez a da formação Gosau, na 
Austria. 
Comquanto alguns Cephalopodes do 
Brazil mostrem intima semelhança com 
alguns dos que caracterizam a fauna cre- 
tacea da parte meridional da America do 
Norte, os Conchiferos, e especialmente 
os Gasteropodes, têm comparativamente 
poucos caracteres communs. Pelo menos, 
relativamente ás duas ultimas classes de 
molluscos, esta fauna brazileira parece 
ter um parentesco tão remoto com a 
fauna cretacea da America do Norte como 
com qualquer fauna do mesmo periodo 
de qualquer outra parte do mundo. Esta 
dissimilhança entre as respectivas faunas 
- cretaceas da America do Sul e do Norte, 
Third, although some of the species have 
a Jurassic aspect, none of them are iden- 
tifiable with any known Jurassic species. 
Finally, as all the collections have been 
shown to belong to one fauna, and a part 
of its species to be certainly of Cretaceous 
age, the whole fauna must necessarily be 
referred to that period. 
The fossils which are described in 
these memoirs represent a fauna which 
presents certain conspicuous differences 
from any of the Cretaceous faunas that 
have been discovered in other parts 
of the world. And vet, as regards 
the molluscan types which they em- 
brace, this Brazilian fauna seems to 
be more nearly related to the Cretaceous 
fauna of Southern India than to any 
other that has yet been investigated. The 
next in similarity is perhaps the fauna of 
the Gosau formation in Austria, 
While some of the Brazilian Cephalo- 
pods are found to bear close resemblance 
to some of those which characterize the 
Cretaceous fauna of Southern North Ame- 
rica, the Conchifers, and especially the 
Gasteropods, have comparatively few 
characteristics in common. As regards 
those two classes of mollusks, at least, 
this Brazilian fauna seems to have as re- 
mote a relationship with the North Ame- 
rican Cretaceous, as with any fauna of 
that period in any other part of the world. 
This dissimilarity between the North 
American and South American Creta- 
ceous faunas respectively, is all the more 
E Sa AN e de a di O a dd ca id dia AR ASS is 
