294 



BULLETIN 76, UNITED STATES NATIONAL MUSEUM. 



Marginiil plates regularly arrangetl. Superomarginal series departing frcm 

 interratlial angle about midway between dorsal center of disk and inner angle of 

 jaw-plates; occasionally rather irregular near interbrachial angle; plates sometimes 

 transversely elongated, with ten to twelve spinelets. Inferomarginals slightly 

 larger or exactly equal to superomarginals ; one or two rows of intermarginal plates 

 on basal fifth of ray; also one or two rows of actinal intermediate plates, two extend- 

 mg about one fifth length of ray, and one series for one half length, beyond which 

 point inferomarginals and adambulacrals are in contact. Intermarginal and 

 inframarginal papulise ; one to six in an area. Marginal plates also form fairly regular 

 transverse series with adambulacrals, although latter are more numerous than 

 former. 



Adambulacral plates mth one small spine deep in furrow; on some plates, 

 especially in large specimens, a second may be present just above it and in line. 

 On actinal surface two blunt, stubby spines stand in an oblique transverse series 

 on furrow margin (frequently a group of three); and beliind them three or four 

 much shorter graduated spinelets in a single zigzag series, all more or less united 

 by membrane. Armature varies greatlj^, sometimes two transverse series of spines 

 being present, and the spines themselves vary in shape from slender, cylindrical 

 and tapering to thick, clavate, and blunt. Ai'mature generally has appearance of 

 being in a single series and rather sparse. The outer spinelets of some specimens 

 (those which have very minute spinelets generally) are buried in membrane and all 

 but invisible. 



Madreporic body variable, usually subtubercular, roundish, with coarse 

 striations. 



Color in life. — Abactinal surface deep chrome yellow; papular areas deep 

 saffron yellow ; actinal surface pale Indian yellow. 



Tyfe.— Cat. No. 21930, U.S.N.M. 



Type-locality. — Albatross station 3052, Heceta Bank, Oregon, 48 fathoms, on 

 coral and broken shells. 



Distrihution. — From Bering Sea (Bering Island, Pribilofs, Aleutian Islands) 

 south along the coast to the Santa Barbara Islands, California. Bathymetrical 

 range, 26 to 313 fathoms. On muddy, sandy, pebbh% shelly, and rocky bottom. 



Specimens examined. — Seventy-six, as follows: 



Specimens of Henricia aspcra examined. 



Nature of bottom. 



2842. 

 2857" 



2864. 

 2865. 

 2875° 

 2877. 

 2887. 

 2958° 

 2965. 



Near Unalaska, Alaska 



Near Afognak Island, Alaska 



Queen Charlotte Sound, British Co- 

 lumbia. 



Admiralty Inlet, Washington 



do 



Off Cape Flattery, Washington 



.do.. 



Heceta Bank, Oregon 



Near Santa Barbara Islands, California 

 09 Santa Barbara 



pebbles 



shells, black specks.. 



mud, broken shells, sand. 



pebbles 



rocks and shells 



black sand, mud 



coral and pebbles 



gray sand 



fine gray sand 



I Not typical. 



U. S. Nat. Mus. 

 Do. 



Do. 

 Do. 



