AFRICA. 157 



Maw, George. Bos primigenius in Algeria. Geol. Mag. dec. ii. 



vol. iii. p. 48. 

 Letter announcing discovery. 



Nachtigal, Dr. Gnst. Voyage dans TAfrique centrale. [Travels in 

 Central Africa, 1809-1874.] Bull. Soc. Geogr. Paris, 6 ser. t. xi. 

 pp. 129-155, 255-277, map (not geological). 



The Tibesti mountains consist in part of granite capped with sand- 

 stone ; and their summit is a vast crater (p. 133). The soil of the 

 Somrai is clayey (p. 151) ; and so is that of the Fettri country (p. 256). 

 Copper is worked at Hofra in Nehas, antimony (formerly) at Mount 

 Marra. Lead occurs in the Djebcl Kouttoum, situate in the Dar el 

 Gharb ; iron in the south-western province. Salt is found in several 

 places (pp. 269, 270). G. A. L. 



Papier, A. Observations sur le memoire de M. Goujon. [Remarks 

 on M. Goujon's paper.] Bull. Ac. Ilijojjone, no. 12, p. 56. (See 

 above.) 



Parisot, Capt. A. V. La region entre Ouargla et El Golea. [The 

 Country between Ouargla and El Golea.] Bull. JSoc. Geogr. Paris, 

 6 ser. t. xii. pp. 577-603. 



Contains many geological notes. The paper is not yet completed. 



Ravenstein, E. G. The Western Sahara. Geogr. Mag. vol. iii. 

 pp. 13-16. 



A sketch of the geography of the Sahara. There are extensive pla- 

 teaux, ranges of mountains, vast belts of sand hills, and several de- 

 jjiessions below the general level. The " sand hills " consist of regu- 

 larly bedded Pliocene rocks (brackish or freshwater), the surface of 

 which has been disintegrated by atmospheric action. F. D. 



Rialle, Girard de. La Mer interieure du Sahara. Ilev. Sci. xi. 

 pp. 409-417. 



A description of M. Iloudaire's expedition to survey the country 

 around the 'chotts:' contains information on the *chotts,' sand- 

 hills, &c. 



Schweinfurth, Dr., and Giissfeldt, Dr. A journey into the Arabian 

 Desei-t of Egypt. Geogr. Mag. vol. iii. pp. 184-186. 



Near the monastery of St. Paul are plutonic and metamorphic rocks, 

 overlain by sandstone, on which lie TJ. Cretaceous rocks with fossils 

 (Echinoderms and Ammonites); upon this is the Eocene formation, 

 which makes the mass of the mountains. F. D. 



Seriziat, Dr. £tudes sur I'Oasis de Biskra. [The Biskra Oasis.] 



Paris. 

 Treats of the hydrology and geology of the Sahara. 



