lii INTRODUCTION. 
and in the autumn of the same year returned to Frankfort. On his second visit 
(1S22) he was accompanied by Surgeon Michael Hey, and on their arrival in Egypt they 
turned their steps towards the Fayum, thence by way of Damietta to Lake Menzaleh, 
and afterwards to Alexandria, where Riippell met Hemprich, the companion of 
Ehrenberg who was then in Dongola. Riippell and his companion Hey then pro- 
ceeded up the Nile to Thebes, whence they made an excursion to Kosseir. They 
afterwards continued their journey to the south as far as Dongola, and after a short 
residence there Riippell returned to Cairo, but when the hot season had passed he 
rejoined his companion. He attempted, in the end of 1823, to reach Kordofan, 
but failed, and returned to Cairo in June 1824. Towards the latter part of that 
year he and his companion again set out for New Dongola. In the end of that 
year Riippell with some of his attendants started for Kordofan across the desert of 
Simri, and on the 13th July, 1825, reached the capital. He remained seven weeks in 
Kordofan and returned to Cairo in the month of July. He was the first scientific 
traveller to visit Kordofan. He spent the first half of the year 1826 on the coast of 
the Gulf of Suez, and Akaba, making long excursions into the country, into the Sinaitic 
Peninsula, and along the coast to El Tor. He also sailed along the coast to Massowah. 
He returned to Europe, arriving at Leyden on the 20th Sept., 1827. In the autumn of 
1830 Riippell, accompanied by Theodore Erckel, set out again for Egypt and made 
another expedition, in the early part of 1831, to the Sinaitic Peninsula, where he spent 
some time. He then proceeded to Massowah, which he reached 17th Sept., 1831, 
and remained in Abyssinia until after the middle of 1833. On his way up the Red Sea 
he stopped at Jiddah, to study its natural history, and remained there apparently for 
some months. Returning to Egypt he resided at Cairo from November 1833 to the 
spring of 1834. when he finally returned to Europe. The results attained by Riippell 
on his excursions in Egypt, including his journey to Kordofan and apparently his 
first visit to Massowah, were described by C. H. G. von Heyden K 
The following species were new to the fauna of the Nile Valley : — 
Hemidactylus yrunosus, Heyden. = Hemidacttjlus t.urcicus (Linn.). 
Agama armaria, Heyden. = Agama sinaita, Heyden. 
Uromastix dispar, Heyden. = Uromastix acanthinurus, Bell. 
Varanus ocellatus, Heyden. 
In 1823, when Riippell was attempting to enter Kordofan, and Hemprich and 
Ehrenberg 2 were conducting their natural-history researches at Damietta, Wilkinson 
and Burton (afterwards Haliburton) were exploring Lower Egypt from an archaeological 
standpoint, but at the same time were not wholly ignoring its fauna, as is evinced by 
their donations to the British Museum. 
1 Atlas nbrdl. Afr., Euppell (1827). 
2 Beisen durch Jvord-Afr. (Ileisen in Aegypten, Libven, Nubien u. Dongala, 1828). 
