of Birds in Southern Kamerun. 561 



these have ripened and burst out, shews that eggs have 

 recently been laid. If these are carefully counted^ tlie 

 number of eggs laid may be seen. By still other indications 

 a sitting bird may be known. The nearly bare tract of 

 skin on the abdomen becomes completely bare and more 

 or less extended at the sides in a sitting bird, and the 

 innermost layer of the skin next the body becomes swollen 

 and watery. 



The Seasons in Southerii Kamerun. 



The temperature here may be said, for practical purposes, 

 not to change at all in the different seasons. But there 

 is a good deal of variation in the rainfall in different 

 months. There is a sort of double year, each half of the 

 year having a dry and a rainy season. The rainy seasons 

 come about the equinoxes, when the sun is directly overhead 

 near the equator, and the dry seasons about the solstices. 

 The times when the dry seasons occur correspond, the one 

 to the dry season in Africa south of the equator, which is 

 at its height in July; and the other to the dry season 

 further north, which is at its height in January. These 

 statements apply to the climate of the southern part of 

 Kamerun only. Even at Duala, only a little north of 

 Kribi, the southern dry season has disappeared, and the 

 months of July and August have become the rainiest of 

 the year. 



I have obtained exact figures for the rainfall in each month 

 at Duala, Kribi, and Ebolwoa, from records kept b}'- officials 

 of the German government (see text- fig. 6, p. 562). At 

 Kribi the rainfall " curve " runs high all through March, 

 April, May, and June; descends in July; but rises again 

 in August, and reaches the highest point of the year in 

 October; and in November descends again, to remain low in 

 December, January, and February. At Ebolwoa it attains 

 its first high point in April, is low all through June, July, 

 and August, and reaches another culmination, the highest of 

 the year, in October. 



At Efulen, my general impressions, from several years' 



