RECENT OPHIURANS. 335 



1331. O. DISACANTHA H. L. Clakk, 1911. BuU. 75 U. S. N. M., p. 102, f. 38. 



6 PAEATYPES. Bering Sea, 45-74 fms. Unalaska: Captain's Harbor, 

 9-14 fms. 



1332. O. TETRACANTHA H. L. Clakk, 1911. Bull. 75 U. S. N. M., p. 104, f. 39. 



39 PAEATYPES. Alaska: Kadiak Island, Chagofka Cove. 

 Ophiothyeexjs. 



Ljxjngmaw, 1871. Ofv. Kongl. Vet.-akad. Forh., 28, p. 619. 

 Type-species: Ophiothyreits goesi Ljungman, 1871. loc. cit. Monotypic. 



1333. O. GOESI Ljitngman, 1871. Ofv. Kongl. Vet.-akad. Forh., 28, p. 619. Koehler, 1904. 



Mem. Soc. zool. France, 17, p. 59, f. 5-7. 



19 specimens, including 2 cotypes. Cuba: off Havana, 80-250 fms. 

 Off Isle of Pines, 300 fms. Off Anguilla, 200 fms. Off Montserrat, 88 fms. 



Amphipholizona, gen. nov. (AmpMpholis + Ophiozona). 



Type-species: Amphipholizona delicala, sp. nov. 



Disk covered by few, large plates and scales. Oral papillae as in Amphi- 

 pholis; i. e., 3 on each side, the distalmost largest, the proximal one block-like 

 and infradental in position. Peristomal plates paired, very large. Genital 

 plates not soldered to basal vertebrae. Tentacle-scales confined to basal arm- 

 joints but tentacles continuous to tip of arm. Second oral tentacles entirely 

 concealed within mouth sht. Genital shts short; no genital papillae and no 

 arm-comb. Arm-spines, at least on basal joints, long and flaring. 



This genus shows a remarkable combination of characters, the oral surface 

 being very amphiurid-like, while the dorsal side of the disk is like Ophiozona. 

 It has seemed best to put it in the Ophiolepididae in view of the characters 

 shown by the disk and the internal plates but it is not very hke to any genus 

 hitherto known in that family, though perhaps most similar to Ophioceramis. 



1334. A. DELICATA, sp. nov. Plate 20, f. 1, 2. 



Disk 3 mm. in diameter; arms nearly 18 nmi. long, relatively wide at base, 

 but tapering soon to an attenuate tip. Disk covered by the radial shields, 16 

 large plates and 15 scales; there is a central plate, 5 radials forming a closed 

 ring around it, and in each interradius, 2 large, squarish, interradials, a distal 

 and a proximal; between each radial plate and each pair of radial shields is a 



