34 MEMOIR OF PALLAS. 
with what we have designated a Monograph of 
Antelopes. Here the general description is some- 
what altered, and sixteen species are enumerated ; 
and to the minute account of the Grim, that of the 
Cervicapra is added ; the second fasciculus contains 
the Apis £thiopicus and the coney or cavia, both 
of which are somewhat further illustrated ; the third 
is wholly occupied with bats, and another new 
species is added, the Cephalotes of Geoffrey ; and 
the last treats of the crane before mentioned, and 
the crested and mitred guinea-fowls of Africa. 
But the work, together with Pallas’s residence in 
Berlin, were brought to a sudden close, by his being 
invited by the Empress Catherine II. to accept of 
the professorship of natural history in the Imperial 
Academy of Sciences at St Petersburg; and although 
in this instance his father and other relatives again 
refused their assent, yet his own ardent zeal for his 
favourite science induced him, without a moment's 
hesitation, to accede to the invitation, and to hasten 
his departure for a country where his curiosity was 
so likely to be amply gratified. He accordingly 
quitted his native land in June 1767, and arrived 
in Petersburg on the 10th of August. 
His stay, however, was likewise very short in 
this capital, as his services were almost immediately 
put in requisition in connexion with an important 
and extended scientific expedition. The reigning 
Empress was excited to promote this measure by a 
somewhat curious circumstance. At the time of 
the transit of Venus over the sun’s disk in 1763, the 
