^Sb <-• SKOTTSBERG 



Chapter XI. 



The Tertiary floras of Chile and Patagonia. 



'rcrtiar\' plant fossils have been discovered in the coast region of south Chile, 

 in Patagonia along the Andes south to the Magellan Straits, and in Tierra del 

 Fuego. The richest localities are on the coast of the province of Arauco, 37°-37°30' 

 s. hit., in combination with the coal seams of Lota, Lebu etc., and east of Lake 

 Xahuclluiapi on the Argentine side. 



I'lu- C 'o)iLt'pcio)i-Ayauco series. — The fossil flora was examined by ILngkliiardt, 

 who described more than one hundred species of angiosperms, and later by BERRY 

 \2j]. The determinations are, just as in all the other cases, based on leaf impres- 

 sions, but although l^l'.KKV found that KxoKLllARDT's determinations "are usually 

 to be relied upon" ({x 75), very many of them are, as well as his own, open to 

 doubt. The species were as a rule referred to living genera, belonging to many 

 more or less important tropical-subtropical families, Annonaceae, Apocynaceae, 

 Hignoniaceae, Bombacaceac, Caesalpiniaceae, Combretaceae, Erythroxylaceae, Lau- 

 raceae, Lec\'thi(.laceae, Myrtaceae, Palmae, Sapindaceae, Styracaceae, Vochysiaceae, 

 and so forth. In general character the flora approaches that of the Amazon basin, 

 e.xtended, the relief of the Andes being low at that time, to the west coast of 

 the continent and reaching south at least to 40° s. lat. The flora contains "no 

 eleiuents of the flora of Central Chile" (p. 106) — Cassia is, however, one of the 

 genera mentioned, another is Myraugcuia, represented by several species in cen- 

 tral and south Chile (to know Myrtaceae without flower and fruit is well-nigh 

 impossible). Hl'kKV referred the flora to the Lower Miocene, "it is surely not so 

 okl as lv)cene", and also younger than the XotJiofagus flora in the Magellanian 

 zone (j). 115); this he considered to be of Low^er Oligocene age. 



There are two gynuiosperm genera in Berrv's list which seem to disturb 

 the imj)ression of an otherwise homogeneous neotropical assemblage, Araucaria 

 and St<//a'i(f. The material was reexamined by FLORIN (pj) who showed that 

 Araiuana ara!/i(>r>fsis Berry is a species of Podocarpus, and Sequoia cJiilensis 

 Fngclhardt p. p. another. These, together with a fern described by HallE (Lygo- 

 ({n())i, ;i2] are important additions to the Arauco flora. F^LORIN, in accordance 

 with l^KrciCl.N, ref(,'rs it to the I'>)cene and characterizes it as follows. 



The ( oinpo.sition of the fossil c:onifer vegetation, and the distributional aspects, of 

 it> < onstitucnts, iii(!i( ;itc that it derives from a \varni-teiuj)crate or sul)troj)ical rain-forest, 

 more particularly a lowland i)od()c.arj)-evcrgreen dicotylous broad-leaved tree forest, 

 growint,' on tin- ( oastal plain or j)erhaps partly on low hills not far from the coast. The 

 ( limatc was ])r()hal)ly ( harac tcri/.ed hy great humidity and rather uniform temperature, 

 it was trostless, and wanner than the i)rescnt climate of the same district (p. 26). 



The possibility that plant material from the uplands had been carried down 

 and become nnxcd with material frf)m the coastal plain is contradicted by the 

 state ol preservation which is the same in all cases (p. 26). 



'I he rhiiileufu flora. — The fossiliferous beds of Rio Pichileufu are situated 

 in 41 s. lat. about 30 miles east of Lake .Xahuelhuapi in a treeless steppe country. 



