OF THE BUREAU OF ETHNOLOGY. XXXI 



This also gives a signification to the birds' heads on the 

 engraved shells found in the mounds of the United States, a 

 full account of which was given by Mr. W. H. Holmes in his 

 paper published in the Second Annual Report of this Bureau. 

 It' this supposition be correct, it not only confirms Mr. Holmes's 

 suggestions, but also indicates that the people who built the 

 mounds followed the same custom in this respect as the Na- 

 huatlan tribes. 



Fourth. Another and more important result is the proof fur- 

 nished of an intimate relation between the Mayan and the 

 Nahuatlan tribes, which suggests an ingenious theory pre- 

 sented, though not insisted upon, by the author. 



ON MASKS, LABRETS, AND CERTAIN ABORIGINAL CUS- 

 TOMS, BY WILLIAM H. DALL. 



Masks have been used by many peoples widely scattered 

 throughout the world, and they have a high historic antiquity. 

 In these masks great diversity of form and structure is ob- 

 served, and the) T have been used for many purposes. Mr. 

 Dall explains the development of the use of masks in the fol- 

 lowing manner : 



Masks were probably at first mere shields or protections to 

 the face, supported by the hand, but afterwards were adapted 

 to the form of the face, and were supported upon the head and 

 shoulders. Impenetrability being the first desideratum, exte- 

 rior appearance or ornamentation was secondary, but subse- 

 quently a moral value was sought in capacity to inspire terror, 

 so that by the increase of devices adding to frightfulness the 

 mechanical value became unimportant. Individual variation 

 then began, embracing personal or tribal insignia, and often 

 connected with totemic and Shamanistic systems. By several 

 lines of evolution masks became on the one hand associated 

 with supernaturalism, filling their place in religious parapher- 

 nalia, and on the other with buffoonery appropriate to public 

 games and noticeable in the paraphernalia of secret associa- 

 tions. When the mask has developed into a social or religious 

 symbol it has sometimes been worn elevated above the head 

 of the wearer to increase apparent height, and, losing the no 

 longer needed apertures for sight and breathing, has become a 



