258 
TIERRA DEL EUEGO AND WEST COAST 
CHAP. 
(such as the Patellae, Fissurellae, Chitons, and Barnacles),, 
according to Mr. G. B. Sowerby, are of a much larger size, and 
of a more vigorous growth, than the analogous species in the 
northern hemisphere. A large Voluta is abundant in southern 
Tierra del Fuego and the Falkland Islands. At Bahia Blanca, 
in lat. 39 0 S., the most abundant shells were three species of 
Oliva (one of large size), one or two Volutas, and a Terebra. 
Now these are amongst the best characterised tropical forms. 
It is doubtful whether even one small species of Oliva exists 
on the southern shores of Europe, and there are no species of 
the two other genera. If a geologist were to find in lat. 39 0 
on the coast of Portugal a bed containing numerous shells 
belonging to three species of Oliva, to a Voluta, and Terebra, 
he would probably assert that the climate at the period of their 
existence must have been tropical; but, judging from South 
America, such an inference might be erroneous. 
The equable, humid, and windy climate of Tierra del Fuego 
extends, with only a small increase of heat, for many degrees 
along the west coast of the continent. The forests, for 600 
miles northward of Cape Horn, have a very similar aspect. As 
a proof of the equable climate, even for 300 or 400 miles still 
farther northward, I may mention that in Chiloe (corresponding 
in latitude with the northern parts of Spain) the peach seldom 
produces fruit, whilst strawberries and apples thrive to perfec¬ 
tion. Even the crops of barley and wheat 1 are often brought 
into the houses to be dried and ripened. At Valdivia (in the 
same latitude of 40 0 with Madrid) grapes and figs ripen, but 
are not common ; olives seldom ripen even partially, and 
oranges not at all. These fruits, in corresponding latitudes in 
Europe, are well known to succeed to perfection ; and even in 
this continent, at the Rio Negro, under nearly the same parallel 
with Valdivia, sweet potatoes (convolvulus) are cultivated ; and 
grapes, figs, olives, oranges, water and musk melons, produce 
abundant fruit. Although the humid and equable climate of 
Chiloe, and of the coast northward and southward of it, is so 
unfavourable to our fruits, yet the native forests, from lat. 45 0 
to 38°, almost rival in luxuriance those of the glowing inter- 
tropical regions. Stately trees of many kinds, with smooth 
and highly coloured barks, are loaded by parasitical monocoty- 
1 Agiieros, Descrip. Hist, de la Prov. de Chiloe, 1791, p. 94. 
