ALLEN: MAMMALS FROM THE BLUE NILE VALLEY. 307 



of the wet season, afPorcl a passage. As settlements increase along the 

 rivers, the native villages are planted at such spots, termed ' mesharats,' 

 or "places where one can get down to the water." Since the large 

 mammals are also dependent on these for reaching the water, the 

 settlements result in driving them farther and farther away where 

 there are 'mesharats' at a distance from habitations, with their 

 accompaniment of droves of cattle, yelping dogs, and native hunters. 



The luxuriant growth of tall grass that springs up after the summer 

 rains becomes exceedingly dry by late autumn, and the natives set fire 

 to it and burn the country for many hundreds of square miles. The 

 soil itself becomes transformed from a mass of sticky mud in the wet 

 season to a hard baked or a powdery condition, often much cracked 

 and very difficult for walking. Such unfavorable conditions appear to 

 have had a direct influence in reducing the ground-living species to a 

 minimum, so that it was very hard to obtain small mammals, and even 

 in comparatively sheltered places the number of species was disap- 

 pointingly few. According to local report, there is much more large 

 game along the Blue Nile during the wet season and just previous to it, 

 in April and May, when the drying up of the smaller and remoter 

 pools forces the animals to seek the main stream. The rank growth of 

 vegetation during the summer rains also causes a more general dis- 

 persal. 



There has been but little collecting done in the area covered, though 

 travellers have from time to time sent specimens to Europe. As long 

 ago as 1842, Sundevall published descriptions of mammals obtained in 

 Sennar by the Swedish traveler Hedenborg, but as then used, Sennar 

 was a somewhat indefinite term applied to the country between the 

 White and the Blue Niles. Ruppell and Heuglin later did much 

 exploration in northeastern Africa, including journeys into the Sudan. 

 They gave names to many of the species whose range includes the Blue 

 Nile country. What has since been done in the study of the mamma- 

 lian fauna of the region has been of fragmentary nature, and consists 

 chiefly of reports on occasional specimens sent by Europeans to the 

 museums of England and Germany. In 1898, Lord Lovat's expedi- 

 tion crossed from southern Abyssinia to the Blue Nile Valley, and 

 obtained a few specimens from the latter region, including a. new 

 multimammate mouse, described by de Winton (1900). Captain 

 S. S. Flower, of the Gizeh Zoological Gardens has several times l)een 

 in the region to obtain living animals for the splendid collection under 

 his charge. Mr. A. L. Butler, head of the Game Preservation Depart- 

 ment of the Sudan, also knows the country well and has sent many 

 specimens of birds and mammals to the British Museum. 



