SOUTH AMERICAN HIPPURITES 
273 
edly new, and one that may be readily recognized by collectors 
from the accompanying illustration, the work of G. S. Barkentin. 
The species may be named 
Hippurites holiviensis, n. sp. 
Attached valves broadly conical, with slightly convex profiles; 
low, the largest about 4 centimeters high and 6 centimeters in 
maximum diameter; elliptical in marginal outline, the minimum 
diameter one centimeter less than the maximum diameter; furrows 
faintly indicated in the two larger forms, but slightly more prom¬ 
inent in the younger form; columnar areas not different in orna¬ 
mentation from the rest of the surface; ornamentation a combin¬ 
ation of transverse, somewhat irregular laminae and upright folds, 
which are faint at the base and become more pronounced upward; 
inner layer of the shell, internal features and cover valves not seen. 
The species shows more or less resemblance to a number of 
south European and north African species of Turonian, Santonian 
and Campanian ages, but in the absence of actual specimens for * 
comparison there is little to be gained by a discussion 'of these 
resemblances derived from a study of illustrations, and besides it 
is believed that there is little of age significance in such resem¬ 
blances. The Bolivian form appears to be clearly referable to 
the genus Hippurites of the family Hippuritidse, although it shows 
some resemblance to certain species of the genus Sphserulites of 
the allied family Radiolitidae, which lacks the smooth bands of 
the genus Radiolites. 
The only previous record of the occurrence of the sub-order or 
super-family Rudistacea in South America appears to be that by 
Fritzsche,^ who records Agria Blumenbachi St. from a number of 
localities in Peru and Chile.^ This he considers to be of Urgonian 
(Barremian) age, from the resemblance to rocks supposed to be 
of that age in East Africa and Persia. Agria is probably a 
Sphaerulites, and hence belongs to the family Radiolitidae. As¬ 
sociated with Agria Fritzsche records what he calls Requienia 
ammonia, Goldfuss, which he seems to consider a Rudistid, al¬ 
though it belongs to the less specialized alliance of Chamacea. 
2 Centralb. f. Geol. Min. & Pal., 1921, No. 9, p. 276, 1921. 
3 These localities are Matash near Huallanca, and Acopampa, near Huarez, in 
Peru; Potrero in the Copiapo Valley, Paso Malo, near Arqueros (ast of L,a Serena) 
and between Arqueros and Rodaito, in Chile. 
