170 GEOLOGICAL RECONNAISSANCE OF THE DOMINICAN REPUBLIC. 



a number of ramifying channels. The river formerly emptied into Man- 

 zanillo Bay, but it now enters the ocean at the southwest end of Monte 

 Cristi Bay, about 3 kilometers from the town of Monte Cristi and 15 kilo- 

 meters north of its former mouth. Its course is said to have been diverted 

 several years ago by the construction of a dam near Las Cafias, about 13 

 kilometers upstream from the present mouth of the river. The dam has 

 apparently concentrated all the water in the present channel, wnich 

 probably was formerly one of many channels that extended across the 

 delta. 



The gradient of the river is about one meter to the kilometer, but the 

 valley is in general a nearly level seaward-sloping plain. In the main 

 valley the eminences that project above the plain are few and incon- 

 spicuous. The surface of the plain rises gradually to the foothills of the 

 Monte Cristi Range on the north and to the Cerros de Jacuba and other 

 outliers of the Cordillera Central on the south. The site of the town of 

 Monte Cristi is bordered on its landward side by a low semicircular ridge 

 and on its seaward side by salt marshes, which are protected from the sea 

 by a low sand bar. The custom house and wharf are at one end of this 

 sand bar. Almost 5 kilometers north of the town is a wedge-shaped butte 

 about 225 meters high, called El Morro. (See PL II, B.) The butte is 

 accessible by land only from the sand bar, for the sea washes its north and 

 west sides and salt marshes stand on its other sides. 



The Monte Cristi Range is composed of irregularly arranged hills 

 and small mountains. Although some of the hills are steep, and even rough, 

 none of them rise to a great altitude. The range was crossed on the trail 

 from Monte Cristi through Isabel de los Torres to the sea at the finca of 

 Sefior Rodriguez, about 25 kilometers northeast of Monte Cristi town, 

 where there is an old rope-fiber factory. Along this trail the range con- 

 sists of isolated hills, 100 meters or more high, which rise abruptly from a 

 rolling terrane that stands probably not much more than 10 meters above 

 sea level. These hills, though rocky, are rounded rather than serrate. 

 The hills southeast of the house of Sefior Rodriguez are higher and the coun- 

 try there is not so open. The trail from this house to Sabana Cruz, after 

 passing Arroyo Guanito, climbs nearly 70 meters up a steep slope called La 

 Subida de la Salina. At the top of this slope is a plain, which stands about 

 170 meters above sea level, and scattered hills rise abruptly 70 to 100 meters 

 higher. This plain extends eastward, though it becomes rolling and more 

 dissected in that direction until it merges into the open valley of Rio Yaque 

 near La Plata. 



The rugged mountains of the Cordillera Central, which bound the valley 

 of Rio Yaque on the south, rise abruptly from the savannas that occupy the 

 area between the main mountain mass and its outliers. Hummocks of 

 gravel are scattered over the savannas. The Cerros de Jacuba, one of the 



