234 BULLETIN 100, UNITED STATES NATIONAL MUSEUM. 



granules, which are especially evident on the specimen represented in 

 figure 1. 



I also give photographs of the dorsal surface of two specimens of 

 Ophiothrix galatheae which are in my collection, both of which come 

 from Billiton; in one of these (pi. 34, fig. 3) the radial shields have 

 the usual dimensions, and are absolutely naked, showing only small 

 blue dots; in the other (fig. 4) these shields are remarkable for their 

 large size; their surface is also entirely naked, and the two shields 

 of each pair are very close together with the internal borders 

 straight. The granules which cover the dorsal surface of the disk 

 in the interradial spaces instead of being short and conical with 

 three or four short and blunt points as usual (pi. 99, fig. la) , are here 

 peculiarly elongated forming true spines with rather elongated 

 points (fig. Ib). 



On the same plate I also show a number of arm spines as well as 

 the tentacle scale. On the first arm segments the first ventral spine 

 (A), which is thick and strong, shows a few asperities which may 

 end in sharp points; it is only at some distance from the disk that 

 these points develop further, while the dimensions of the spine be- 

 come somewhat reduced (g) ; when the transformation into a hook 

 is complete (/) this first spine is also greatly reduced in size, and 

 usually shows four elongated and rather well-spaced points; the 

 terminal point, which forms the extremity of the hook, is a little 

 stouter than the three others, which remain subequal. This form 

 of hook is different from that seen in 0. longipeda, 0. hirsuta, and 

 O. puncto-limbata. The tentacle scale is large and rounded, and it 

 bears on its free border a few conical and subequal points (i) . 



Ophiothrix galatheae has been found in numerous localities in the 

 Indo-Pacific region. 



OPHIOTHRIX HIRSUTA Muller and Troschel. 



Plate 31, figs. 1, 2 ; plate 33, fig. 13 ; plate 99, fig. 2. 

 See for bibliography : 



Ophiothrix hirsuta KCEHLEB ('05), p. 93; ('07), p. 333; ('07b), p. 252. MAC- 

 INTOSH ('11), p. 93. H. L. CLARK ('15), p. 272. MATSUMOTO ('17), 

 p. 225. 



Locality. Albatross station 5174; in the vicinity of Jolo; Jolo 

 Light bearing E., 4.82 kilometers (2.6 miles) distant (lat. 6 03' 45" 

 N., long. 120 57' 00" E.) ; 36 meters (20 fathoms) ; March 5, 1908. 



One specimen (Cat. E. 338, U.S.N.M.). 



Notes. The general color of the specimen in alcohol is gray ; the 

 radial shields are lighter, with small blue spots; a series of small 

 blue spots runs along the distal border of each upper arm plate. 

 The radial shields show only small and closely crowded granules 



