140 



SEXUAL SELECTION: BIRDS. 



[Part II. 



spot (5), with its bright shading, there is a long, narrow, 

 black mark (c), belonging to the same row, and which is 

 arched a little downward so as to face (b). It is also 

 narrowly edged on the lower side with a fulvous tint. To 

 the left of and above c, in the same oblique direction, but 



Fig. 58. — Portion of one of the Secondary wing-feathers near to the body ; show 

 ing the so-called elliptic ornaments. The rio;ht-hand figure is given merely 

 as a diagram for the sake of the letters of reference. 



A, B, C, etc. Rows of spots runnins: 

 down to and forming the elliptic 

 ornaments. 



b. Lowest spot or mark in row B. 



c. The next succeeding spot or mark 



in the same row. 



d. Apparently a broken prolongation 



of the spot c in the same row B. 



always more or less distinct from it, there is another black 

 mark (d). This mark is generally sub-triangular and ir- 

 regular in shape, but in the one lettered in the diagram is 

 unusually narrow, elongated, and regular. It apparently 

 consists of a lateral and broken prolongation of the mark 

 (c), as I infer from traces of similar prolongations from 

 the succeeding upper spots ; but I do not feel sure of this. 



