NO. 1823 NOTES 269 



Stone of Kentucky. In the number of localities and exquisite 

 preservation of the material, the Ivlississippian or Subcarboniferous 

 strata of Kentucky have the best representation. The lowest strata 

 of this larger group, the Kinderhook Knobstone shales, are well 

 exposed near Lebanon, Kentucky, so that naturally the number of 

 species from this horizon is particularly large. 



From a biologic standpoint, the brachiopods of the collection are 

 especially noteworthy. Several years ago a biologic series of this 

 class of organisms was started in the division of invertebrate paleon- 

 tology ; today, by selecting series of specimens from the Ulrich and 

 Rominger collections, and now from the Pate collection presented by 

 Mr. Springer, the number of species of post-Cambrian Paleozoic 

 forms has increased to such an extent that 80 standard drawers are 

 required to contain them. This, combined with the collection of 

 Cambrian brachiopods, makes the National collection unrivaled. — 

 R. S. BassIvER. 



Sound Signaling by Indians oe Tropical South America 



For a long time early travelers through tropical South America 

 were at a loss to know how the Indians at the villages along the 

 streams (all travel being by river, of course) were always prepared 

 for them, seeming to know the number of their party, number of 

 canoes, their destination, etc., and it was finally learned that these 

 savages had solved the problem of immediate communication to 

 their own satisfaction and for their own daily use and comfort. It 

 is a well-known fact that the North American Indians of the Great 

 Plains communicated with each other over long distances. Theirs, 

 however, was a sight system of signaling, usually by smoke in day- 

 time and fire by night. Such a system was impossible for the Indians 

 of tropical South America because of miles of dense forests in a 

 country of no mountains or eminences of any great height. By exer- 

 cising their ingenuity, however, a system of signaling by sound, 

 crude in a way, and yet very efifective, has been perfected among 

 them by which they communicate with each other, though many 

 miles apart. A rough sketch of one of the most successful of these 

 signaling devices, which I saw in operation, is reproduced herewith. 



The apparatus consists usually of two logs of about six and seven 

 feet in length and twelve and fifteen inches in diameter, of a wood 

 similar to the corkwood, of which the balsas, or huge rafts, com- 

 moiily used on the river, are made. By means of hot stones, two 

 holes, connected by a long narrow canal, are burned into the logs, 

 and through these holes the logs are later hollowed out bv the 



