FRIEDRICH WELWITSCH. - 
September, and first became acquainted with a thoroughly tropical 
vegetation. He reached Loanda, the capital of Angola, in -the 
beginning of October, 1853, and making that town the base of his 
operations, he at once undertook excursions in eve ry direction, collect- 
a her 
will 
in the ‘‘ Proceedings of the Linn. Soc.,’’ vol ii., p. res He devoted 
nearly a year to the thorough investigation of this maritime zone, 
and then started for the interior, following the course of the Bengo. 
Having reached the district of Golungo-Alto, he fixed himself at a 
place in its centre, about 125 miles from the coast, and situated in a 
mountainous region, called Sange, whence he made expeditions, often 
extended to great distances. Two years were spent here in these 
arduous oxptaneibiad through almost impenetrable forests, during 
which Dr. Welwitsch wiiffored repeatedly and severely from "endemic 
fevers, scurvy, and ulcerated legs, the usual concomitants of African 
travel ; but he never abandoned his work. It was during his resi- 
dence at San . Welwitsch made the acquaintance of Dr 
ivingstone, then (October, 1854) on his way Loanda, g 
lled the ce from Cape elle 
lived together for some , and the meeting had the effect of deter- 
mi Dr. tsch on relinquis a he had previously 
entertaine to make his across the continent 
known, a successfully accomplished during the two follow- 
ing yea 
"in 1856 Dr. Welwitsch left Golungo-Alto, and travelling south- 
west through the district of Ambaca, which he found full of novelties, 
reached that of Pungo-Andongo in October. Of this stage of his ex- 
a 
paper on the “ Black Rocks” of the district, from which it received 
its old name of the Presidio das Pedras negras. The annual blacken- 
ing after each rainy season of these masses of gneiss, 300 to 600 feet 
in height, he found to be caused by the immense increase and spread 
wnwards 
vegetation, from the various districts of ec and sub-tropical 
Africa, judiciously grouped together, with fm considerable number of 
forms of vegetation quite peculiar to itself.” 
Making this paradise a centre, he passed cht months in travers- 
* It was here that Rhipsalis Cassytha, Gartn., the only Cactacea hitherto found 
out of America, was discovered. 
