PERMO-CARBONIFEROUS GLACIAL DEPOSITS 2k 
the aid of two young Brazilian geologists, Eusebio Oliviera and 
Juvenal Pacheca, is admirable and has served as guide in a portion 
of my own work." In the following year H. Bross confirmed his 
conclusions, finding striated stones near Itararé.? 
Up to r911r Permo-Carboniferous tillite had been reported from 
southern Brazil only; but in that year T. G. Halle described tillite 
of the same age from the Falkland Islands, which may be looked 
on as belonging to the South American region. In rorz2 tillite 
with polished and striated stones, including bowlders up to 1.5 
meters in diameter, was described by C. Guillemain, from Uruguay;! 
and in 1913 J. Keidel announced the finding of tillite of this age in 
southern and western Argentina in a paper read before the Twelfth 
Geological Congress in Toronto; while in 1916 he gave an excellent 
and full account of the tillite at Sierra de la Ventana in southern 
Argentina.® 
From this outline of the literature on the Permo-Carboniferous 
glaciation in South America it will be seen that our knowledge of 
the distribution of the tillite is rapidly growing, extending now to 
three countries, and that this glacial formation is widely spread in 
southern Brazil and perhaps also in Argentina. In Brazil the 
excellent field work of Oliviera and Pacheca is constantly extending 
the known area of glaciation, so that in this respect South America 
may soon rival South Africa and Australia and surpass India. 
It was planned to visit localities for tillite in several parts of 
Brazil and at Sierra de la Ventana in Argentina, and these plans 
were carried out successfully, largely through the help and advice 
of Pacheca in Sao Paulo and of Keidel at Buenos Aires. I am 
specially indebted to Dr. Pacheca, who has mapped the tillite in 
detail in the state of Sao Paulo, and who showed me a number of 
tJ. B. Woodworth, Bull. Mus. Comp. Zool., Harvard, LVI, No. 1, Geol. Series, X. 
Geol. Exped. to Brazil and Chile. 
2 H. Bross, “Glacial Spuren in Parana,” Cent. Bl. fiir Min., etc., 1909, pp. 558-61. 
3T. G. Halle, Geol. Mag., N.S., V, 264-65; also Bull. Geol. Inst., Univ. Uppsala, 
XI, 144-56. 
4C. Guillemain, Neues Jahrb. fiir Min., etc., Beilk Band XXXIII, 208-64. 
5 J. Keidel, Comptes Rendus, pp. 676-80; also in La Geologia de las Sierras de la 
Provincia de Buenos Ayres, Tomo XI, No. 3, Anales del Ministerio de Agricultura of 
the Argentine Republic, 1916. 
