100 BLIND VERTEBRATES AND THEIR EYES. 



water is encountered in a crescent-shaped pool. The caves extend down for ai 

 indeterminable distance below the water-level. The surface of the water in th< 

 caves is near sea-level. Light penetrates to all the recesses of these caves, one o 

 which is called Cueva clos Insurrectos from the fact that a company of Cuban: 

 was quartered in it during the Revolution. Figure B, plate n, gives a glimpst 

 down the Cave of the Insurrectos from the entrance X in figure 68 to the pool o: 

 water at the bottom, at a vertical distance of 83 feet. These caves are inhabitec 

 by Slygtcola, but in very much fewer numbers than the well near the seashore 

 One specimen was secured. 



A cave in the side of the hill at the edge of Matanzas shows essentially the same 

 character. The slope is very much steeper and the cave is much smaller. There 

 is the same sort of pool at the bottom as in the Cave of the Insurrectos. I secured 

 no fishes in the Matanzas Cave, though it probably contains them. We were told 

 that into this cave the Cubans, shot during the Revolution, were thrown by the 

 guardians of Matanzas. 



On the southern slope of the island, both at Alacranes and westward aboul 

 Cafias, are formations very much like each other and very much like the condition 

 represented in figure 68, with these exceptions : the territory is farther from the 

 sea ; the pockets corroded in the surface rocks are much deeper and larger, and are 

 filled with a stiff red clay. 



Bananas are grown in the pockets of soil about the caves at Alacranes. Aboul 

 Cafias most of the territory is still in its primitive condition, covered with manigua, 

 a straight-stemmed, smooth-barked, but irregular-surfaced, sapling that grows in 

 such abundance mingled with other bushes and vines that it obscures the nature oi 

 the' ground and makes progress through it impossible without the machete. 



Frequent clearings made to convert the manigua into charcoal and prepare the 

 soil for seed tobacco reveals the nature of ground to be a series of jagged rocks with 

 pits and depressions filled with the aforesaid red clay. The roads through this 

 region are simply trails along which the manigua has been removed. The rocks 

 are in the natural condition or worn a little by the two-wheeled vehicles which 

 alone are usable here. The wheels of these are so large that they bridge most of 

 the pits between rocks. Traveling over the roads in the manigua in one of the two- 

 wheelers is quite a serious performance. Where the soil is a little thicker, tobacco, 

 casava, and other things are grown. I do not know whether the formation is con- 

 tinuous from Cafias to Alacranes, but it seems quite certain that we have to deal 

 with the same sort of structure in both places. It is a raised coral beach somewhat 

 shattered and with a thin, in many cases interrupted, layer of soil. 



The entire southern slope of the area from Alacranes and Union to Canas is 

 drained by underground streams which, for the most part, are inaccessible. The 

 underground drainage begins further north than the northern edge of the manigua. 

 At San Antonia de los Banos ' a stream is seen to enter the ground, and a few yards 

 Irom tliis place, where the thin limestone roof of the underground channel has 

 given way, the stream can be seen. (See frontispiece.) 



I ''or reasons to be mentioned at once the streams are inaccessible. In August 

 ol i no i a ury heavy rain caused a small torrent to run in the road leading south 

 from Cafias for a distance of about a mile to the Finca Rosa, where the water 

 d out over a depression of several acres, so shallow that the depression was 



I'hr rlrvation of llie railroad track is 62.92 m. 



