OPHIUKANS OF THE PHILIPPINE AND ADJACENT WATERS. 239 



Notes. — The two specimens are of small size ; the diameter of the 

 disk in one is 5 mm. and in the other 3.5 mm. The coloration recalls 

 that which I have recorded in certain specimens from the Siboga 

 collection, from stations 64 and 153. In the larger, the general color 

 is roseate ; the dorsal surface of the disk shows somewhat wavy pur- 

 ple lines, the upper arm plates show a red spot in the center and also 

 a dark line along their distal border, and the spines are dark red. 

 The second is lighter ; the dorsal surface of the disk shows large red 

 spots, one in the central region and the others covering a part of the 

 radial shields; the upper arm plates are uniformly red; the spines 

 are light gray or slightly roseate. 



Ophiothrix foveolata is not always easily recognized, and I have 

 thought it worth while to give here for comparative purposes in addi- 

 tion to the photographs of the specimens collected by the Albatross 

 (figs. 4, 5, 6) a photograph of the dorsal surface of one of the Siboga 

 specimens in which the general appearance is somewhat different from 

 that of the two specimens which I have just mentioned (fig. 7) ; in this 

 individual the general coloration is grayish, and the dorsal surface of 

 the disk shows only a few dark blue lines on the borders of the radial 

 shields, or a few small spots of the same color on the shields them- 

 selves, as well as in the interradial spaces. 



On plate 98, as figure 6c, I show the first ventral arm spine, which 

 transforms rapidly into a hook of the typical form with three,, 

 or sometimes with only two, branches, two tentacle scales («.), and 

 some arm spines (b and d). 



The type of 0. forveolata came from the Aru Islands. The Siboga 

 met with it in many localities in the Sunda Archipelago at depths be- 

 tween 9 and 141 meters (5 to 77 fathoms). The species also has been 

 recorded from the Mergui archipelago. 



OPHIOTHRIX HYBRIDA H. L. Clark. 



Plate 46, figs. 4-6 ; plate 99, fig. 3. 

 Ophiothrix hylrida H. L. Clark ('15), p. 272, pi. 12, fig. 5. 



Locality. — Albatross station 5321 ; China Sea, in the vicinity of 

 Formosa; Ibugos Island (south end) bearing S. 89° W., 2.32 kilo- 

 meters (1.25 miles) distant (lat. 20° 19' 30" N., long. 121° 51' 15" 

 E.) ; 47 meters (26 fathoms) ; November 9, 1908; wh. S., Co., brk. Sh, 



One specimen (Cat. No. E. 56, U.S.N.M.). 



Notes. — The diameter of the disk is 10 mm. ; the arms are all incom- 

 plete, and one of them is preserved for a length of only 50 mm.; 

 they must have been very long. 



Ophiothrix hybrida was recently described by H. L. Clark from a 

 unique specimen, and he considered it a hybrid between O. trili- 

 neata and O. longipeda, believing that it shared the characters of 



