220 CRUISE OF THE BARRERA 



mogotes and rocky patches, forming the attenuated 

 southern end of the range. Just how far they 

 extend — if to the coast — we do not know, but 

 probably traces of them might be found evenjnto 

 the Ensenada de Cortes. 



Back of the inn at Mendoza is one of these 

 small mogotes from which the road builders are 

 blasting out a pure white limestone for road mac- 

 adam. We regarded it with hungry eyes, for this 

 would be our only chance to try out some col- 

 lecting in this range. We bolted breakfast and 

 made a dash for the spot with a time-allowance of 

 just one hour before our train was due. The hour 

 was well spent, for we fell upon a remarkably inter- 

 esting lot of land-shells, among which was the 

 extraordinary Urocoptis dautzenhergiana. The re- 

 ported habitat of this very locally distributed 

 snail is the large mountain of "Paso Real de 

 Guane" and we had not counted upon the good 

 fortune of finding it upon a small isolated mogote. 

 We caught our train by a second's margin. The 

 railroad passes east through the sierra belt where 

 the elevations are eroded down to merely a rocky 

 region of huge limestone boulders, vine-covered, 

 and very appealing as collecting stations. The 



