272 
SOUTH AMERICAN HIPPURITES 
HIPPURITES FROM SOUTH AMERICA" 
By Prof. Edward W. Bfrry 
Johns Hopkins University, Baltimore 
It is an appropriate commentary on the lack of geological 
knowledge of the greater part of South America that the recent 
Williams Expedition should have obtained but two specimens of 
fossils from the Bolivian altaplanicie between Lake Titicaca and 
La Paz, and that each of these forms should represent a different 
Late Cretacic marine type new to South America, and from a reg¬ 
ion where no Cretacic rocks have ever been recognized, a tract 
moreover, more traveled than any other that could be mentioned 
in that general region. 
The first of these types, a new species of the typical Late Cre¬ 
tacic echinoid genus Echinocorys, was described in a recent note. 
It was picked up by natives at Penas, about 56 km. northwest of 
La Paz, and about 10 km. from the eastern shore of the Laguna 
Uinamarca — the southern and small division of Lake Titicaca, 
from which it is almost entirely severed by the peninsulas of Co- 
pacabana and Hachacache. 
The second specimen was also collected by natives and came 
from detrital material in the valley of the Rio Milluni, a small 
stream taking its origin in the Devonic tract of the southern 
slopes of Huayna Potosi and flowing into the Rio Vilahaque 12 
km. northwest of La Paz. I am indebted to Senor Arturo Poz- 
nansky, the director of the Institute Tihuanacu for this valuable 
specimen. The latter owes its preservation to the fact thatjt is 
encased in an argillaceous, marcasite-impregnated concretion. It 
shows the surface features of three individuals of the genus Hip- 
purites. The material displays the attached valves; and although 
these are not sufficient for complete diagnosis, the form is undoubt- 
1 George Huntington Williams Memorial Publications, No. 11. 
