4 U.S. NATIONAL MUSEUM BULLETIN 2 75 



larger wadis (dry watercourses). Vegetation also occurs sparingly 

 along the margins of the sand seas. Some of the mountainous com- 

 plexes support scattered growths of grasses, and others are almost 

 devoid of vegetation. The oases of the Libyan Sahara support ex- 

 tensive groves of date palms and other agricultural crops and appear 

 as verdant areas in the midst of their barren surroundings. 



The climate of most of Libya is typically Saharan and extremely 

 arid but is more humid in the coastal areas. As a result of their higher 

 elevations and greater amounts of rainfall, the Tripolitanian Gebel 

 and the Cyrenaican Plateau are local exceptions and have cooler 

 climates. 



Explorations in Libya date from the end of the 18th century, but 

 zoological information did not begin to accumulate until the end of 

 the 19th century. Among the earliest publications relating to the 

 rodent fauna of Libya and adjacent countries are those of Yarrel 

 (1831), Loche (1867), Lataste (1881 and 1887), Nehring (1897), and 

 Sordelli (1899). The 20th century marked the beginning of any real 

 definitive studies of Libyan rodents. Most prominent among these 

 workers during the early part of this century are: Thomas (1902- 

 1925), Klaptocz (1909), Andreucci (1914), Ghigi (1920), Festa (1921 

 and 1925), Hartert (1923), Hinton (1926), and de Beaux (1928, 1932, 

 and 1938). More recently Zavattari (1934 and 1937), Heim de Balsac 

 (1935), Rode (1948), and Toschi (1951 and 1954) have published 

 papers dealing with various aspects of the Libyan rodent fauna. 

 Setzer (1956 and 1957) is the most recent worker on Libyan mammals. 



Prior to the present study, relatively few specimens of Libyan 

 mammals were available, and the systematic composition and distri- 

 bution of the rodent fauna were accordingly poorly known. Specimens 

 collected by the Whitaker Expedition to Tripolitania and the Fezzan 

 in 1901 (reported by Thomas in 1902), those collected by de Beaux's 

 expeditions to Giarabub and Cufra in 1928 and 1932, and those ob- 

 tained by Toschi in 1951 and 1954, constituted the most significant 

 collections of Libyan rodents prior to 1955. 



This study of Libyan rodents is based primarily on specimens ob- 

 tained by the author during the period from October 1961 to July 

 1962. 



Field work consisted of approximately 10 months of intensive 

 collecting in various parts of the three provinces of Libya. During 

 this period efforts were made to obtain adequate series of representa- 

 tive rodents from all types of habitats. 



The duration of each collecting trip ranged from 1 week to 3 months. 

 One to 14 days were spent at eacli collecting site. The majority of 

 specimens were obtained by using approximately 200 museum special 



