498 THE DESCENT OF MAN. 



from it, there is another hlack mark (d). This mark is 

 generally sub-triangular and irregular in shape, but in the 

 one lettered in the diagram it is unusually narrow, elon- 

 gated and regular. It apparently consists of a lateral and 

 broken prolongation of the mark (c), together with its con- 

 fluence with a broken and prolonged part of the next spot 

 above; but I do not feel sure of this. These three marks, 

 (b)) (c) and (d), with the intervening bright shades, form 

 together the so-called elliptic ornament. These ornaments 

 placed parallel to the shaft, manifestly correspond in posi- 

 tion with the ball-and-socket ocelli. Their extremely ele- 

 gant appearance cannot be appreciated in the drawing, as 

 the orange and leaden tints, contrasting so well with the 

 black marks, cannot be shown. 



Between one of the elliptic ornaments and a perfect 

 ball-and-socket ocellus the gradation is so perfect that it is 

 scarcely possible to decide when the latter term ought to be 

 used. The passage from the one into the other is effected 

 by the elongation and greater curvature in the opposite 

 directions of the lower black mark (b fig. 59), and more 

 especially of the upper one (c), together with the contrac- 

 tion of the elongated sub-triangular or narrow mark ^d), so 

 that at last these three marks become confluent, forming an 

 irregular elliptic ring. This ring is gradually rendered 

 more and more circular and regular, increasing at the same 

 time in diameter. I have here given a drawing (fig. 60) of 

 the natural size of an ocellus not as yet quite perfect. 

 The lower part of the black ring is much more curved than is 

 the lower mark in the elliptic ornament (b fig. 59). The 

 upper part of the ring consists of two or three separate 

 portions; and there is only a trace of the thickening of the 

 portion which forms the black mark above the white shade. 

 This white shade itself is not as yet much concentrated; 

 and beneath it the surface is brighter colored than in a per- 

 fect ball-and-socket ocellus. Even in the most perfect 

 ocelli traces of the junction of three or four elongated 

 black marks, by which the ring has been formed, may often 

 be detected. The irregular sub-triangular or narrow mark 

 (d fig. 59), manifestly forms, by its contraction and equal- 

 ization, the thickened portion of the ring above the white 

 shade on a perfect ball-and-socket ocellus. The lower part 

 of the ring is invariably a little thicker than the other 

 parts (see fig. 57), and this follows from the lower black 



