NARRATIVE OF THE CRUISE. 



395 



I do not think that it can properly be relegated to any genus at present defined, but it 

 will doubtless fall into its place when the Ophiurids shall have been revised. 



" The disk is about 20 mm. in diameter; and the arms are four times the diameter of 

 the disk in length. The disk is uniformly coarsely granulated ; the arm-shields, which 

 are well defined through the membrane, are rounded in form and roughly granulated 

 like the remainder of the disk. The character which at once distinguishes this species 

 from all the others of the genus is, that the normal number of the arms is six or seven 

 instead of five, which is almost universal in the class. The number of arms is subject 



Fig. 150. — Opkiaeantha vivipara, Ljiinstiiian. Falkland Islamls. Twice the natural size. 



to certain variation. I have seen from six to nine, but never fewer than six. The 

 arm-spines are numerous and long. The general colour of the disk and arms is a dull 

 greenish brown. 



"A large proportion of the mature females, if not all of them, had a group of from 

 three to ten or twelve young ones clinging to the upper surface of the disk by their arms : 

 the largest of these were about a quarter the size of their mother ; and they graduated 

 down in size until the smallest had a diameter of less than 1*5 mm. across the disk. 

 The largest and oldest of the progeny were always uppermost, farthest from the disk, the 



