202 COMMENTARY ON THE PLANTS IN 
which the plants and fruits made up the fourth volume); and accom- 
panied with a repetition of the Brazilian name, and a reference to 
Maregrav and Piso for further information* ; the smaller collection - 
in water-colours being always quoted, whenever the same subject oc- 
curs in it. M. Lichtenstein considers it, from various reasons, as 
highly probable, that this last-mentioned collection, which the Count 
of Nassau had in common use, and which contained his own notes, 
was the produce of Maregrav's pencil. It is called “ Liber principis” 
in the Royal Library. All these most precious materials are at present 
in the Royal Library at Berlin, and entered in the catalogue of manu- 
scripts under the head of libri picturati in folio, A. num. 35. There is 
besides a copy of Maregrav's work, with the woodeuts coloured from 
those originals, which M. Lichtenstein conjectures to have been likewise 
the Prince's own copy. The directors of the Berlin Royal Library have, 
with literary liberality, granted me permission to have oil copies taken 
of the figures of plants in the Theatr. rer. nat. Brasilize, on paper as in 
the originals, and guaranteed as regards their fidelity, by the fact, that 
Messrs. Ehrenberg and von Schlechtendal superintended their execu- 
tion. In this manner have I been placed in possession of the richest 
possible literary apparatus, for illustrating those early labours in the 
flora of Brazil. 
One thing, however, is still wanting to the commentator, which 
would have been extremely desirable in his inquiries, namely a com- 
plete view of the vegetations of the regions where Piso and Maregrav 
pursued their labours; for it happens to be precisely the territory 
from the southward of Ceará to the great Rio de S. Francisco, which 
has hitherto been least visited by botanists ; and the materials gathered 
there have only in a slight proportion become a common stock among 
botanists. Though three native Pernambucans have occupied them- : 
selves, in the first decades of the present century, with the flora of their 
country, the results contribute only little to the solution of our problem, 
and it will therefore suffice for literary and historical purposes simply 
to notice them heref. Manoel Arruda da Camara has published three 
works treating of the plants of those regions: Memoria sobre a cultura 
* The title which Mentzel gave these volumes is: Theatrum rerum naturalium 
Brasilia. 
+ Compare my view of the authors on the Flora of Brazil, in supplement to 
Allgemeine Bot. Zeitung, 1837, vol. ii. p. 13. 
