Apkii. S, 1883.1
��275
��nearlj horlioiilal strain) of [lie Brazilisn plalemi
are those of the Parntia, AniaKotiaa, Sao Fmnctico,
unci Pitnialiyba baaina. That of the Parana hasiii,
which may be considered as embracing the Uruguay,
intiudes a iarge portion of the jirovinces ol Rio
Grande
Siil, Santa Cntharins, Pamni!, and SHo
Paulo; a smail part of south-neeCeru Miniu Geraes
and soutbern Goyaz; and Ihe elevated portion of the
province of Matto Grosso, and of the repiiblic of
FaragLiay, lyhig between the Parana and Paraguay.
The maximum elevation along the eastern bordi^r in
the provinces ot Parani and Siio Paulo is approxi-
mately 1,000 metres, tUc general level becoming a
few hundred metres lower to the southward and
westward, as the result not only of denudation, but
also of a general lowering of the surface.
The Amazonian tablelniid includes the greater
part of the provinces of Matto Grosso and Goyaz, a
large part of southern Panl, and relatively small
portions of soutli-easlem Amazonas and western
Maranbao. It Is drained by the Tocan tins- Araguaya,
Xingii, Tapajds, and lower Madeira, with its tribu-
tary the Guapor^, all of which descend from the
tableland iti a series of rapida, at a distance of from
100 to 200 miles from the Amazonas. The louthern
mai^ln of this great tableland — an escarpment ris-
ing to betwecTi 800 and 1,000 metres above the level
of the sea. and facing the depression of tlio Paraguay
and Guaporg — has received the name of Serra dos
The Sao Francisco tableland lies mainly to the
west of Ihat river, in the western part of the prov-
inces of Minas Geraes and Bahia, and rises to the
height of about 800 metres. It is doubtful whether
or not it extends over the watershed, so as to be coii-
tinuous with those of the Tocantins and Pamahyba
volleys. The latter occupies all, or nearly all, of the
province of Piauhy, and a portion of soulheni Mar-
anhlUi and western Cearii, and is perhaps continuous
with the Amazonian tableland along the Tocantins
divide.
All of these tablelands ore dee|>Iy cut by numer-
ous river-valleys so as to present almost everywhere
a mountainous aspect; and the ridgea formed by
denudation are generally spoken of as mountains,
and are represented as such on all maps of the em-
pire.
The Brazilian portion of the Guiana plateau Is
very Imperfectly known. Along the watershed be-
tween the Amazonas and the rivers flowing lo the
Caribbean Sea there are monntaius whose culminat-
ing poinW are said to rise lo the elevation of 3,000
metres or more; and spurs of high lands extend to
within a few miles of the Amaxonns at several points
between the month of the Rio Negro and the sea.
This region is drained by ilie Rio Negro, with its
tributary the Hio Branco, and a number of smaller
rivers, amonft which the JanmniW, Trombetas, Pard,
Jary. and Araguary are the most Important.
The great Amazonian depression Is relatively nar-
row along the lower river, below the mouth of the
Rio Negro, the average width being probably between
100 and SOO miles. Above the Rio Negro and Madeira,
��in the province of Amaznnus, it widens conttiderably,
so that it presents a bottle or flask shape. The river
is generally bordered by low alluvial plains, often of
considemble width, which are subject to overflow,
and are full of lakes and anastomosing liile-ebannels
of the great river, or of the lower courses of Its tribu-
taries. The higher lands are either tablelands less
than 300 metres In height, formed by deposits pe-
culiar to the depression, or denuded outhers of the
mai^ins of th: great continental plateaus an either
side, or of the Andean plateau at the head of the
The Brazilian part of the Paraguay depression
is the upper portion of the immense plains ot the
basin of that river, which form a large part of the
Argentine Republic, Paraguay, and easieni Bolivia.
These plains lie several hundred raetrei lower than
the lands of the platean that encircle tbem, and of
Its numerous spurs and outhers. They are. for the
mobt part, but slightly elevated above the level of
the rivers (Ihe upper Paraguay and its tributaries)
that [ravene them, and, during the wet season, be-
come traiisformed into immense lakes and marshes.
The Atlantic border-region consists of a zone, gen-
erally only a few miles In width, lying between the
coast and the margin of the continental plateau.
South of Rlode Janeiro It is constituted by low sand-
plains full of lagoons, and by denuded spurs and
outhers of the plateau. North of Rio de Janeiro
there arc in many places. In addition to these, hills
and tablelands of formations peculiar to tliis const-
belt, which rite to a height of from 100 to 200 metres.
O. A, Dkhbv.
��I
���AccoRDiNo to a late report by Lieut. -Commander
Z. L. Tanner, U.S.N., commanding the U.S. Bsh-
eoinmlssion steamer Albatross, dated at New Orieans,
Feb. 13, the recent short cruise ot that vessel has
been productive of some interesting n
The Albatross left Washington on the afternoon
of the day before Christmas (1884), and after
delay by Ice In the river, and by rough weather in
Chesapeake Bay, arrived at Norfolk on the morning
of the 26th. Having taken in coal at Norfolk, and
received the parly of naturalists detailed for Ibe
cruise,' she put to sea on the afternoon of Jan. 3
(1885), bound for Key West. At stariing, the very
unusually high barometer of 31.10 was noted; but
the glass began falling early next morning, with tl)D
setting-in of a smart soulh-ensi gale and heavy sea.
On the 6th, the weather having moderated, r
line was set for tlle-Hsb, in 111 fathoms oft the Car-
olina coast, but without result. Four hauls with
the beam-trawl, with wlng-nels and mud-bags, in
about the same locality, were more productive, bring-
ing up many familiar species, and some new to the
ship.
' Mi. J. K. Btn.
T>r)^lod H. lleui, anJ Mr. Tliornu
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