OBSERVATIONS ON TYPHLOMOLGE RATHBUNI. 87 



ditions, and conducted a most extensive search for Typhlomolgc. 

 Hence the scarcity of this species is somewhat perplexing. It is 

 possible that the animals prefer to stay further down in the 

 passages and cracks filled completely with water under high pres- 

 sure, an assumption which is supported by the circumstances 

 under which the animals were found in both the artesian well and 

 Frank Johnson's Well. It may be that they rarely and only by 

 some incidental circumstances are induced to come to the more 

 open bodies of water. 



So far as is known to the writer, the specimen of Typhlomolge 

 caught in Ezell's Cave in 1916 is the first and only one positively 

 known as having come from this locality. But it is claimed by 

 people in San Marcos, as Mr. S. N. Stanfield, teacher of biology 

 in the Texas Normal School in San Marcos, informed me, that 

 the first two Typhlomolge ever seen were found in Ezell's Cave, 

 i Y-2. years before the well was drilled, in a small boat, which 

 had sunk in Ezell's Cave Lake. 



BEAVER CAVE. 



Not far from the entrance of Ezell's Cave on the southwest 

 slope of San Marcos Hill and at an altitude of 652 feet above sea 

 level, near the dry bed of the City Boundary Creek is situated the 

 entrance to Beaver or Wonder Cave. The location of the cave 

 would indicate that it belongs, like Ezell's Cave, to the Purgatory 

 Creek System. 



Beaver Cave represents the aspect of a straight running crack 

 in the strata of the Edwards limestone, the same as Ezell's Cave ; 

 this crack, in part, has been widened out and its walls have been 

 smoothed down by the action of the water (Fig. 10). Its bottom 

 is made up of huge masses of broken-down rocks which form, at 

 some places, high cliffs and rock masses, dividing the entire cave 

 horizontally in a number of rooms connected by narrower tubes 

 with one another, and vertically into several compartments. Fig. 

 II represents a diagrammatic longitudinal section through the 

 cave, which gives an idea of the construction of this cave. In 

 Fig. 10, which was taken parallel to the longitudinal axis, the slit- 

 like shape of the cave is shown ; it can also be seen how smooth 



