144 



BUREAU or AMERICAN ETHNOLOGY 



[bull. 52 



^V/. 



stone and finished with a pressure implement. Practically all of 



the well-developed forms are of leaf-blade genesis, specialization having 



taken different directions according to the implement to be made. 

 The few scrapers were made from flakes of 

 proximate shape and correspond closely in 

 type with the duck-bill scrapers of the white 

 quartzite and pebble groups. The plano- 

 convex knife-blades and the spikelike forms 

 so common in the white quartzite and shore- 

 pebble groups are of rare occurrence. Incip- 

 ient blades unfinished or rejected because of 

 imperfect fracture, of which there are numer- 

 ous examples, are shown in figure 40, and 

 a series of forms illustrating the relation of 

 the first step in the shaping work to the more 

 finished and specialized forms is given in figure 

 41. The ruder specimens are sometimes re- 

 ferred to as "paleolithic," but without other 

 reason than that they are not well-finished. 

 It is not assumed that the final form in this 

 series is the only one that may have been 

 employed as an implement, but the lack of 

 specialization or careful finish of point or edge 

 in the ruder forms supports the assumption 

 that these were not finished implements. 



A representative series of the arrowheads 

 appears in plate 13 and a typical drill-point 



or awl is shown in figure 42. 



To the North American student the most striking characteristic of 



these flaked forms is their remarkable . _, . . 



analogy with North American types. 



The entire collection from the Rio 



Negro could be thrown together with 



corresponding collections from Ari- 

 zona, Georgia, or New Jersey with the 



practical certainty that the student 



would be unable to separate more than 



a few of the specimens of the several 



regions. 



Fig. 37. Pestles, (i actual 

 size.) o, Quartzite pestle of 

 cigar shape (San Bias Dis- 

 trict), b, Sandstone pestle, 

 fragment (San Bias District). 



Fig. 38. Axlike blade of sandstone, bear- 

 ing engraved design (factual size.) Pu- 

 erto San Bias. 



ETHNIC BEARING 



A study of the lithic art of the region under consideration brings 

 into prominence the fact that three groups of chipped artifacts, pre- 

 senting certain noteworthy resemblances and differences, are repre- 

 sented. These groups are the hammer-anvil worked pebbles of the 



