NORTH PACIFIC OPHIURANS IN NATIONAL MUSEUM CLARK. 217 



mud, bottom temperature 35.9°, 4 s])e("imens; station 5023, Okhotsk 

 Sea, lat. 48° 43' 30" N.; long. 145° 3' E., 75 fathoms, sand, pebbles, 

 bottom temperature 30.9°, 1 specimen; station 5033, Yezo Strait, lat. 

 44° 4' 20" N.; long. 145° 28' E., 533 fathoms, green mud, fine black 

 sand, bottom temperature 35.9°, 1 specimen; station 5036, south of 

 Hokkaido, lat. 41° 58' N. ; long. 142° 30' 30" E., 464 fathoms, brown 

 mud, bottom temperature 37.9°, 2 specimens; station 5082, off Omai 

 S«ki, lat. 34° 5' N.; long. 137° 59' E., 662 fathoms, green mud, fine 

 sand, globigerina, bottom temperature 37.7°, 76 specimens; station 

 5083, off Omai Saki, lat. 34° 4' 20" X.: long. 137° 57' 30'' E., 624 

 fathoms, fine gray sand, globigerina. bottom temperature 38.1°, 3 

 specimens; station 5085, Sagami Bay, lat. 35° 6' 45" N.; long. 139° 

 19' 45" E., 622 fathoms, green mud, line black sand, bottom tempera- 

 ture 37.8°, 2 specimens; station 5087, Sagami Bay, lat. 35° 9' 40" 

 N.; long. 139° 19' 5" E., 614 fathoms, green mud, bottom temperature 

 37.5°, 1 specimen. Xo label, 12 specimens. Batlmnetrical range, 

 40 to 987 fathoms. Temperature range, 55.9° to 30.9°. Three thou- 

 sand nine hundred and fifty-nine specimens. 



The above list is sufficient evidence of the abundance of this species 

 in the north Pacific, but in spite of this abundance and the great 

 geographical and bathymetrical range, it shows remarkable con- 

 stancy in its specific characters. Among all these thousands of 

 specimens, ranging in disk diameter from 3^ to 22 mm., there are no 

 notable variations and the individual diversitv shown is vei'v slierht. 

 One specimen from station 3696 is, however, perfect!}' tetramerous. 

 In specimens under 8 mm. disk diameter there are only three arm 

 spines, but even in the largest specimens the fourth spine is found 

 only on the basal joints of the arm. The extent to which the disk 

 scales are concealed by the granules, the size and pointedness of the 

 granules, the number of granules on the upper arm plates, the form 

 of the under arm plates and the shape of the teeth are the principal 

 features in which a normal amount of diversity is shown. Lyman, 

 in his final report on the Challenger ophiurans, transferred this species 

 to OpJiiomitra, but subsequent writers have, as a rule, considered it 

 as more properly an Ophiacantha, and it certainly seems to belong in 

 that genus, in a broad sense. According to Verrill's classification, 

 it would be a veiy typical member of his proposed genus Ophialc^a. 



OPHIACANTHA CATALEIMMOIDA, new species.a 



Disk 17 mm. in diameter; arms about 75 to 80 mm. long. Disk 

 covered more or less spareely with coai-se, rounded granules, as in 

 norniani. Radial shields, as in that species, with distal half bare, 



" Ka-aXscfi/ioc, signifying relictus, and ddof, signifying/or/??, in reference to the general 

 resemblance to 0. relicta Koehler. 



