110 



COLUMBIAN HISTORICAL EXPOSITION AT MADRID. 



Class A is pointed at both ends. They are widest from one-third to one-fourth 

 the distance from the base. Eleven specimens. 



Class B is more oval, more or less pointed, with concave, straight, or convex base. 

 Five specimens. 



Class C is long, narrow, with parallel edges, concave, straight, or convex bases, 

 and belongs principally to the Pacific Coast. Five specimens. 



II. Triangular. This division includes all specimens which, according to geo 

 metric nomenclature, are in the form of a triangle, whether the bases or edges 

 be convex, straight, or concave. They are without stems and, consequently, 

 without shoulders, although in some specimens the extreme concavity of the 

 base produces barbs. Eleven specimens. 



A 



A B 



LEAF SHAPED 



TRIANGULAR. 



A 



STEMMED 



C D 



PECULIAR FORMS 



Fig. 27. 



FORMS OF ARROW AND SPEARHEADS. 



III. Stemmed. This division includes all varieties of stems, whether straight, 

 pointed, or expanding, round or flat, whether the bases or edges are convex, 

 straight, or concave. 



Class A is lozenge shaped, stemmed, but not shouldered nor barbed. Eight 



specimens. 



Class B is stemmed and shouldered, but not barbed. Sixteen specimens. 

 Class C is stemmed, shouldered, and barbed. Nine specimens. 



IV. Peculiar forms. This division includes all forms not belonging to the three 

 others, and provides for those having peculiarities, or which are restricted in 

 number or locality. 



Class A, beveled edges. Seven specimens. 

 Class B, serrated edges. Six specimens. 

 Class C, bifurcated stems. Seven specimens. 



