OPHIURANS OF THE PHILIPPINE AND ADJACENT WATERS. 159 



become abruptly smaller; there is a very sharp line of demarca- 

 tion between these smaller marginal plates and those which cover 

 the rest of the dorsal surface of the disk. The upper arm plates 

 also have a form slightly different from those in the specimen from 

 the National Museum. But I notice that their form is exactly the 

 same as that which Liitken and Mortensen have shown in one of 

 their figures ('99, pi. 12, fig. 6), while the specimen from the 

 National Museum has the dorsal plates identical with those which 

 these authors have represented in plate 12 as figure 2. All the other 

 characters agree well with those of A. diomedeae. I believe, there- 

 fore, that I am able to assign all my specimens to this species. 



Amphiura diomedeae appears to have a vast geographical range. 

 Liitken and Mortensen described it from specimens found between 

 7-22 N. latitude and 79-107 W. longitude, at depths varying 

 between 935 and 2,877 meters (511 and 1,573 fathoms). The speci- 

 mens of Amphiura diomedeae which II. L. Clark has studied came 

 from numerous localities in the Japanese seas (Honshu Island, 

 Kagoshima, Suruga Gulf, Sagami Bay, Omai Saki, etc.) and from 

 depths between 71 and 1,369 meters (39 and 749 fathoms). The 

 Albatross specimens which I have mentioned above were captured 

 between 9-18 N. latitude and 120-123 E. longitude, at depths 

 varying from 368 to 567 meters (201 to 310 fathoms). 



Matsumoto considers A. diomedeae a synonym of A. koreae Dun- 

 can ('17, p. 198) and believes that the former name should be sup- 

 pressed. He is apparently right, but as it is very difficult to recog- 

 nize the species described by Duncan from his description, and 

 especially from his figures, which are quite inadequate, it would 

 be necessary, in order to be certain, to examine Duncan's type. So, 

 in the absence of more definite information, I prefer to use the 

 name diomedeae given to a species well described and well figured. 



AMPHIURA GRANDISQUAMA Lyman. 



Plate 66, figs. 6-8. 



See for bibliography : 



Amphiura grandisquama KCEHLEB ('09), p. 177; ('14), p. 63. H. L. CLARK 

 ('15), p. 266. 



Localities. Albatross station 5348; Palawan Passage; Point 

 Tabonan bearing S. 89 E., 62.08 kilometers (33.5 miles) distant 

 (lat. 10 57' 45" N., long. 118 38' 15" E.) I; 686 meters (375 

 fathoms) ; December 27, 1908; Co., S. 



Thirteen specimens (Cat, Nos. 41277, 41278, U.S.N.M.). 



Albatross station 5413; between Cebu and Bohol; Lauis Point 

 Light bearing N. 68 W., 18.53 kilometers (10 miles) distant (lat. 



