OPHIURANS OF THE PHILIPPINE AND ADJACENT WATERS. 313 



as broad with the sides almost straight and the angles slightly 

 rounded. The first dorsal arm spine is a little shorter than the 

 following, but it is thicker, though without ever becoming swollen. 



Ophiocoma alexandri. — This species, from the west coast of Cen- 

 tral America and Lower California, is well known through Lyman's 

 excellent description which unfortunately was not accompanied by a 

 figure; but H. L. Clark has just given two photographs ('15, pi. 16, 

 figs. 5, 6) of it. Ophiocoma alexandri does not appear to show much 

 variation; in a specimen which I have in my collection the tentacle 

 scales are two in number as far as the sixth segment (inclusive) on 

 one of the arms; the mouth shields are almost circular, though they 

 may be considered as triangular with the angles very rounded. 



Ophiocoma valenciae. — This species occurs throughout the whole 

 Indo-Pacific region, from the Bed Sea, the east coast of Africa, 

 Madagascar, Mauritius, and the neighboring regions to the Maldive, 

 Laccadive, and Mergui Archipelagoes, the Fiji Islands, and Samoa. 

 The descriptions of Miiller and Troschel and of Liitken have been 

 supplemented by the remarks of Loriol ('93, p. 30) , Marktanner, ('87, 

 p. 303), and Macintosh ('11, p. 160) ; very recently H. L. Clark has 

 given very good photographs of it ('15, pi. 16, figs. 7, 8). Ophio- 

 coma valenciae does not show much variation ; in a specimen which I 

 have from the Red Sea the granules of the disk are rather large on 

 the dorsal surface, and at the periphery they elongate into very short 

 spines of which the point is rounded and which pass over onto the 

 ventral surface where they become slightly more elongated. The 

 mouth shields, which are very much rounded, are as long as broad, 

 as is also shown in H. L. Clark's photograph. In another specimen 

 from the Mergui Archipelago the mouth shields, here also very 

 rounded, are distinctly a little broader than long, and the arm spines 

 are six in number at the base of the arms, the number then falling 

 to five; it is not the second dorsal spine but the third which is the 

 longest. I find two tentacle scales on the two first pairs of pores 

 only, and a single one throughout the remainder of the arms. 



Ophiocoma schdnleini. — I am not familiar with this species, as I 

 have never handled it. Lyman considered it doubtful as he also did 

 O. wendtii, but very recently H. L. Clark ('08, p. 296) found in a 

 collection from Amboina three quite characteristic specimens of O. 

 schdnleini which he described and of which he published later two 

 photographs ('15, pi. 15, figs. 1, 2). H. L. Clark considers 0. schon- 

 leini as very close to O. erinaceus; it is distinguished from the latter 

 by the presence of a single tentacle scale on all the arm segments and 

 of two on the pores of the first pair, sometimes on those of the second, 

 and even of the third; the arm spines are shorter and the mouth 

 shields are slightly broader than in O. erinaceus. According to the 

 same author O. schdnleini is distinguished from O. loendtii by having 



