146 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL, I28 



Three small specimens of Ophiacantha hidentata (Retzius) were 

 dredged at 175, 741, and 477 feet. The one from the latter depth 

 was filled with eggs. This species is new to the western Arctic. 



Collections comprising a few to large numbers of Ophiopholis 

 aculeata (Retzius) were made from no to 741 feet, 20 to 30 speci- 

 mens being obtained from 125, 130, and 217 feet. This species begins 

 reproducing when it is less than half grown. From the well-filled 

 condition of the gonads throughout August and the first week of 

 September, it would appear that either spawning occurs after the 

 first part of September or the eggs are retained until spring. 



About 20 specimens of Amphiodia craterodmeta H. L. Clark were 

 taken in 12 hauls from depths of no to 741 feet. Only one specimen 

 was found well filled with eggs (on October 6, 1949). This is the 

 first record from Arctic Alaska. 



Over 100 specimens of Amphiura sundevalli (Miiller and Troschel) 

 were dredged from depths of no to 741 feet. They were found in 

 interstices among other animals, often among the branches of the 

 bryozoan Myriosoiim subgracile. The condition of the gonads indi- 

 cates that this species spawns during the latter part of August and 

 in September. It is new to Arctic Alaska. 



Ophiura sarsi Lutken was probably the most abundant of the 

 ophiurans, but, since its habitat is a soft substratum beyond shallow 

 water, it was limited to 477 and 741 feet in the area investigated. 

 Evidence indicated that this species had spawned by the middle of 

 August. 



A single specimen of the circumboreal O. nodosa Liitken was 

 dredged at 152 feet. 



At least 70 specimens of O. robusta (Ayres), with disks from 2.9 

 to 10.8 mm. in diameter, were dredged at 16 stations at depths of 

 no to 741 feet. Individuals with disks less than 5.5 mm. in diameter 

 were juveniles. 



Class ECHINOIDEA 



Only one echinoid, Strongylocentrotus drobachiensis (O. F. Miil- 

 ler), was found at Point Barrow, where it occurred at eight stations 

 from 125 to 522 feet, being most abundant at 125 feet (approximately 

 175 specimens) and at 130 feet (September 15, 1948, 73 specimens). 



Class HOLOTHUROIDEA 



Two species of sea cucumbers that have been identified were ex- 

 ceedingly abundant ; the three to five unidentified forms were seldom 

 taken. 



