138 



THE OPHIURIDiE. 



I 



tentacle pores. They are just in contact. No ventral plates beyond the 

 third. Side arm-plates from the third joint closely soldered together in 

 their whole length ; on the dorsal side they are broadly in contact from the 

 first joint. Their sides almost straight ) the outer edge makes a fine curve 

 (couA^ex inwards) across the under side of the arm ; on the sides of the arm 

 it is rather prominent. Dorsal plates very small, triangular, with outer edge 

 strongly rounded. They continue almost to the end of the arm. At the 

 arm basis, outside and between the outer ends of the radial shields, there 

 are some small, irregular plates, whereof the median row must be regarded 

 as rudimentai^ dorsal plates. 



Disk covered with small but distinct, irregular, polygonal scales, among 

 which the primary plates are not distinct except the central plate. Radial 

 shields ^Qvy large, more than half the radius of the disk, separated by a 

 single row of scales, two of which are rather large ; between their inner 

 ends are some more irregularly placed scales. Each interbrachial space is 

 occupied by a double row of scales and by a large marginal plate, which 

 connects the radial shields of each two adjoining arms. Under side of the 

 disk covered by several small and large, irregular polygonal flat scales, 

 among which one outside the mouth shield is most conspicuous; usually 

 it joins the outer edge of the mouth shield. Genital scale rather large, end- 

 ing at the third arm joint. Genital slits very narrow, reaching only to the 

 second, in some specimens to the third joint; the inner end is curved. No 

 genital papilla). Under side of disk and arms quite flat ; the dorsal side is 

 rounded towards the ventral side ; the edge of the disk, which is not sharp, 



is thus at the level of the ventral side. 



Six to eight small, rudimentary arm-spines; the second from below is 

 a little larger and almost covers the first. On the outer part of the arm the 

 spines have the form of booklets. Only two pairs of tentacle pores, the first 

 with one or two oval tentacle scales at the outer side, the second with one. 



The whole dorsal side of the disk and the side arm-plates above and on 

 the sides of the arm beset with a close granulation, which is most developed on 

 the radial shields, the marginal plate, and the side arm-plates. The granuloe 

 on the other scales of the disk are much smaller and inconspicuous. The 

 edges of the radial shields are smooth 5 the side arm-plates have the granulre 

 only along the upper and outer edge. The whole underside is perfectly 

 smooth ; only on the large plate outside the mouth shield there may be a 



single tubercle. 



Color in alcohol: gray. , 



