OPHIUKANS OF THE PHILIPPINE AND ADJACENT WATERS. 329 



where else there is only a single scale, which is rather large and 

 rounded in- form. 



In another specimen, which is a little larger, and in which the 

 disk has a diameter of 14 mm., the majority of the pores of the four 

 first segments have two scales each, and a single pore of the fifth 

 pair also has two of them; all the others have only a single scale, 

 which remains single throughout the length of the arms. 



Specimens as typical as those from Samoa and as those which I 

 described in 1905 and 1907 are easily determinable, and there is no 

 difficulty in referring them to O. wendtii; but because of the .varia- 

 tions which I have described above under O. scolopendrina, it may 

 happen that the determination of certain individuals offers some 

 difficulty. Knowing that in 0. scolopendrina the tentacle scales may 

 sometimes be single after the first two or three arm segments and that 

 the dorsal spines become thickened in certain specimens, one may be 

 led to ask whether individuals showing these peculiarities should be 

 assigned to O. scolopendrina or to O. wendtii. I may say that in 

 this case I am stating a purely gratuitous hypothesis, and that I have 

 never had the slightest hesitation in referring such a specimen either 

 to one or to the other of the two species. The dorsal spines of 

 O. wendtii, even when they are not thickened, are always more elon- 

 gated than in O. scolopendrina; furthermore, the mouth shields of 

 the former species are always very much longer and narrower than 

 in the latter, while the tentacle scale is larger. Thus no doubt can 

 arise ; nevertheless, it is worth while to draw attention to this point. 



OPHIOMASTIX ANNULOSA (Lamarck). 



Plate 72, figs. 4, 5. 



See for bibliography : 



Ophiomastix annulosa KCEHLER ('05), p. 65; ('07), p. 329. H. L. CLARK 

 ('08), p. 297; ('15), p. 294. MATSUMOTO -('17), p. 350. 



Localities. Nasugbu, Luzon ; reef ; January 16, 1908. 



Two specimens (Cat. No. E. 228, U.S.N.M.). 



Jolo, Jolo Island ; March 6, 1908. 



One specimen (Cat. No. E. 227, U.S.N.M.). 



Notes. Although the species is frequent in collections, there are 

 no good figures of it. The colored figure published by Herklots ('68, 

 pi. 4, fig. 1) gives a good idea of the color in the living state, but it 

 does not show the elegant ornamentation of the disk and of the arms. 

 I have thought it well to reproduce here two photographs of the speci- 

 men from Nasugbu, in which the characteristic designs shown by the 

 different parts of the body appear clearly. 



Matsumoto also has just published a few figures of O. annulosa 

 (17, p. 350, fig. 99). 



