248 BULLETIN 100, UNITED STATES NATIONAL MUSEUM. 



different from the more delicate and finer scale which I find in O r 

 lepida^ 



Loriol has stated that O. lepida was without a tentacle scale ('93, 

 p. 47), and he says the same thing for O. fallax (p. 48) ; this state- 

 ment is not correct. This scale certainly is present ; I have described 

 its characters above and I include photographs of it (pi. 100, fig. 

 35 ) . To be sure, this scale may be lacking on certain segments, but 

 I believe that this absence is accidental. The tentacle scale can not be 

 confused with the first ventral arm spine, for the latter, which is very 

 much more elongated, is always easily recognized and furthermore it 

 transforms into a hook a short distance from the base of the arms. 

 After having stated that the tentacle scale is lacking in 0. lepida 

 and O. fallax, Loriol has allowed an error to remain in the figures 

 which he has published of these two species (pi. 25, figs. Id and 2c) 

 showing the ventral surface of the arms. These figures show a very 

 large, broad, and oval tentacle scale of a size that would be quite un- 

 usual in an Ophiothrix; evidently the artist should have represented 

 a pore in place of this scale. 



I may mention that in 1898 ('98, p. 102) I wrote that O. fallax was 

 perhaps only a variety of O. lepida; my opinion on that subject has 

 not been changed. 



The type of O. lepida came from Mauritius. The species was re- 

 discovered by the Investigator in the Andaman Islands and in the 

 Laccadive and Mergui Archipelagoes at depths varying between 15 

 and 50 fathoms. 



OPEIOTHKIX MARENZELLERI Kcehler. 



Plate 39, figs. 3-5 ; plate 100, fig. 4. 



Ophiothrix marenzelleri K<ehler ('04a), p. 103, figs. 76-78. — H. L. Clark 

 ('15), p. 281— Matsumoto ('17), p. 220. 



Locality. — Yenoshima, Japan. 



One specimen (Cat. No. 41024, U.S.N.M.). 



Notes. — I refer to Ophiothrix marenzelleri a single specimen of 

 smaller size than those upon which I originally based the species ; the 

 diameter of the disk is 6 mm., and the length of the arms varies be- 

 tween 25 mm. and 30 mm. The dorsal surface is uniformly covered 

 with elongated and rather thick club spines, to which might almost 

 be given the name of spines; these club spines are cylindrical or 

 slightly conical, smooth, and ending in short, unequal, and thick 

 spinules varying from two to four in number (pi. 100, fig. 4a) ; they 

 are very closely crowded and almost entirely cover the radial shields. 

 These club spines become a little longer, but less closely crowded, on 

 the ventral surface of the disk which they cover in large part, with- 

 out, however, extending as far as the mouth shields or the genital 

 slits. 



