OPHIURANS OF THE PHILIPPINE AND ADJACENT WATERS. 191 



mouth shields are rather large, broader than long, almost biconvex or 

 lozenge-shaped, with the angles and the sides rounded. Their distal 

 angle is produced into a narrow, but rather elongated, lobe, which 

 projects more or less strongly into the interradial space. Martens 

 says that these shields are " kreisformig," but I do not see why he 

 adds " nicht untereinander zusammenhangend." The adoral plates 

 are confined to the sides of the mouth shields; they are extremely 

 attenuated inwardly and do not reach the median interradial line, 

 while outwardly they are developed into a much elongated lobe which 

 goes to meet that of its fellow, and may even touch it in the median 

 radial line, thus completely separating the first under arm plate 

 from the second. This form of the adoral plates may be recognized, 

 though with difficulty, on H. L. Clark's photograph. The oral plates 

 are small, twice as high as broad. They carry a terminal unpaired 

 mouth papilla which is transversely broadened. The second papilla, 

 which is situated toward the proximal extremity of the adoral plate, 

 is much broadened, squamiform, twice as long as broad, with the 

 free border rounded. 



The upper arm plates are extremely broad ; they seem to me to be 

 relatively a little broader in my specimen than in H. L. Clark's; 

 this evidently is correlated with the difference in size, the disk having 

 in the last a diameter of only 4 mm. These plates are almost four 

 times as long as broad, with the two longer sides parallel ; the proxi- 

 mal border is a little shorter than the distal, into which it passes 

 by slightly divergent sides and over rounded angles. All of these 

 plates are broadly in contcat. 



The first under arm plate is rather small, triangular, with the apex 

 distal; it is a little broader than long and separated from the sec- 

 ond, as I have said above. This last is quadrangular, a little longer 

 than broad, with the proximal border a little smaller than the distal. 

 Beyond, the plates rapidly become broader than long, with the 

 proximal side slightly shorter than the distal, and the latter passing 

 over by rounded angles into the lateral sides, which are also rounded. 

 All these plates are broadly in contact. 



The side arm plates, which project only slightly, are not greatly 

 developed, especially on the dorsal side, where they only cover a very 

 reduced portion of the arms. They bear four short thick arm spines 

 with the tip rounded, the size of which increases slightly from the 

 first ventral to the last dorsal, and of which the length almost equals 

 that of the segment. 



The tentacle scale is rather large and elongated, with the two sides 

 parallel, and the tip rounded ; it is half again as long as broad. 



The general color is a light greenish yellow, with a few slightly 

 marked spots on the dorsal surface of the disk, and indications of 

 rings on the dorsal surface of the arms. 



