194 



BLIND VERTEBRATES AND THED* EYES. 



very frequently there is an island in the water beneath the opening in the roof, 

 and in the Ashton type the water has become restricted to a crescent at the base of 

 the wall still standing. It is possible that the Carboneria and Alacranes caves 

 belong to the latter type of caves. 



Almost invariably one or more trees (Ficus) stand over the cave and send long 

 roots down through the cave to the water below, where they break up into number- 

 less rootlets (plate 12, fig. a). The roots were very useful in gaining access to the 

 bottom of some of the caves. During my earlier trips, access was gained to most 

 of the dome-shaped caves by climbing down the roots or a bamboo pole. In the 

 later trips the roots were still the most effective ladders to some of the caves, but I 

 substituted a portable rope ladder for the slippery bamboo pole. 





Flo. 71. Partial North and South Section through Cave Region about Canas, Cuba. Entire area has subterranean drainage. 

 Road from Canas becomes a stream in heavy rains and sinks within the area inclosed in circle. Caves marked with small 

 circles were located by traverse readings, those marked x were located by guess. There are caves south of area mapped, 

 but land slopes to ocean so that water is found very near surface. There are many others in area covered that are not 

 indicated on this map. 



The density of the caves may be gathered from the accompanying sketch of a sec- 

 tion extending south from the station Canas on the Western Railroad but not quite 

 to the southern edge of the cave region (fig. 71). The caves marked with a cipher 

 (o) were located by traverse readings by Dr. Joshua William Beede, of the Geo- 

 logical Department of Indiana University, who volunteered his services on one of the 

 trips. The caves marked with a star (x) were "discovered" on a subsequent visit 

 and located by estimate. Numerous "wells" and other caves are not indicated, 

 but from the number located an idea of the abundance of the caves can be formed. 

 They are about as numerous as sink holes in the cave regions of Indiana and 

 Kentucky. There are caves south of the area mapped, but the land slopes to the 

 ocean 15 miles to the south, so that water is found very near the surface. 



