346 General Notes. 
with shallow grooves, which issue abruptly near the median 
border and radiate towards, and some of them to, the circumfer- 
ence, becoming shallowed externally; no tuberosities. | Diameter 
of scutum, 45 mm.; of median area, 17 mm.; thickness, 15 mm, 
This species is of the same type as that one found in the valley of 
Mexico, but I cannot speak positively as to its identity. It may 
be called Glyptodon petaliferus—E. D. Cope. 
GENERAL.—<According to A. W. Stelzner, the Archean rocks, 
primitive gneiss, and primitive slates compose the greater part of 
the sierras which rise out of the Pampas; but granite occurs in most 
of these sierras, especially in that of Achala. This granite must 
certainly be pre-Silurian. The principal locality of the Silurian 
rocks is in the Anti-Cordilleras. Devonian and Carboniferous rocks. 
Jurassic or to the Cretaceous. Rhætic beds have been found near 
Mendoza and in the Famatina Mountain, etc. Jurassic beds are 
exposed in the Espinazito Mountains, and a Jurassic sea extended 
from the eastern coast far into the interior. The gypsum-bearing 
sandstone of the passes of Patos and Cumbre belong to the Creta- 
ceous formation, as do also the red sandstone of the Province of 
Tucuman and that of Jujuy. 
show 
inextricable confusion ; conglomerates are so compressed that the 
pebbles form narrow lines; granite forms dykes in diorite, and the 
whole region is a maze of conflicting strikes and dips. 
Canozorc.—The ninth volume of the Bulletin of the National 
Academy of Sciences of Cordoba (Argentine Republic) contains 
descriptions of numerous mammalian fossils from the Tertiary strata 
near the Parana. Among these are Cynonasua argentina, a form 
allied to the coati, but with seven molars in the lower jaw ; a Canis, 
of about the size of C. azare; a catlike animal, for which Ame- 
ghini forms the genus Apera, and which appears to have been about 
twice the size of the domestic cat; six species of the rodent genus 
egamys,—one of them of almost gigantic size; Epiblema horri- 
dula, a rodent a little larger than the viscachia ; two or three species- 
