CHAPTEE XVIII. 



Division of Nicaragua into three Zones Journey from Juigalpa to 

 Lake of Nicaragua Voyage on Lake Fresh-water Shells and 

 Insects Similarity of Fresh-water productions all over the 

 world Distribution of European Land and Fresh-water Shells 

 Discussion of the reasons why Fresh- water productions have 

 varied less than those of the Land and of the Sea. 



I SHALL ask my readers to accompany me on one more 

 journey. I have described the great Atlantic forest that 

 clothes the whole of the eastern side of Nicaragua. I 

 have gone through the central provinces, Chontales, 

 Matagalpa, and Segovia ; from the San Juan, river, the 

 south-eastern boundary of Nicaragua, away to the con- 

 fines of Honduras on the north-west. I now propose to 

 leave the central provinces, amongst which we have so 

 long lingered, and to describe one of my journeys to those 

 lying between the great lakes and the Pacific. 



Whilst the country to the north-east of the lakes is 

 mostly composed of rocks, of great age, geologically, such 

 as schists, quartzites, and old dolerytic rocks, with newer 

 but still ancient trachytes, that to the south-west of them 

 is composed principally of recent volcanic tufas and lavas, 

 the irruption of which has not yet ceased. Most of the 

 land, resulting from the decomposition of the tufas, is of 

 extreme fertility ; and, therefore, we find on the Pacific 

 side of Nicaragua, indigo, coffee, sugar, cacao, and tobacco 

 growing with the greatest luxuriance. 



