136, ZOOLOGICAL RESEARCHES « 



The highest temperature in the sun we ever stated , i. e. 

 on an open plain, was 115°. 



I need hardly to say that such a hot-house-temperature, 

 together with the general climate and the abundance of 

 water, is to produce an extremely rich flora and fauna. 

 An exception from this rule is made by the coast-region 

 whose flora and fauna is generally rather poor. Only the 

 inner slope of the low strand-dune is covered with thorny 

 shrubs and the long creepers of a fine Convolvulus. The 

 seashore is visited , during the dry season , by three spe- 

 cies of sea-tortoises {Dermatochelys coriacea, Chelonia midas 

 and Ch. imbricata), which bury their globular, parchment- 

 covered eggs in the dry sand at the back of the dune. 

 Large flocks of Sternae and now and then a pair of Rhyn- 

 chops jïavirostris are seen flying above the surf, and but 

 few shells of sea-mollusks , star-fishes and the like are left 

 behind by the retiring tide. Some species of crabs {Oci/- 

 pode cursor and 0. africana) not differing in color from 

 the yellowish gray sand , run quickly along the seashore , 

 while another species , Grapsus maculatus , is found on 

 rocks washed by the foaming surf, probably feeding upon 

 different kinds of mollusks , as Patella , Fissurella , Hipp- 

 onyx and Littorina with which these rocks are literally 

 covered. The sandbanks before the mouths of the rivers 

 and the banks of rivers and lagunes are, throughout the 

 year, peopled with Alligators (CrocoJilus frontatus) and 

 Iguanos [Monitor stellatus)^ with flocks of Charadrine and 

 Scolopacine birds , especially Numenius phaeopus and Te- 

 tanus canescens , and wild Ducks [Dendrocygna viduata) , 

 with Haliaetus angolensis and , more distant from the 

 water , with Oedicnemus vermiculatus. 



The large swamp-region and the marshy banks of the 

 rivers, as far as they are influenced by the tide, are co- 

 vered with impenetrable Mangrove-forests which make , 

 especially when seen from a distant , somewhat elevated 

 point , an exceedingly sinister impression. These Mang- 

 rove-forests , where sweet and salt water is mixed together 



r*5'otes from the I^eyden Museum, "Vol. VII. 



