270 



BULLETIN 75, UNITED STATES NATIONAL MUSEUM. 



bottom temperature 55.9, 2 specimens; station 4895, Eastern Sea, 

 lat. 32 33' 10" N.; long. 128 32' 10" E., 95 fathoms, green sand, 

 broken shells, pebbles, bottom temperature 55.9, 2 specimens; sta- 

 tion 5070, Suruga Gulf, lat. 35 3' 25" N.; long. 138 47' 40" E., 108 

 fathoms, mud, sand, broken shells, bottom temperature 57. 6, 2 

 specimens. 



Type. Cat. No. 25585, U.S.N.M., from station 4895. 



The transverse spiny bands on the upper side of the arms will 

 readily distinguish this species from all of its allies. The specimens 

 before me have a disk diameter ranging from 5 to 20 mm. 



OPHIOBYRSA SYNAPTACANTHA, new species, a 



Disk 12 mm. in diameter; arms about 220 mm. long. Disk covered 

 by skin containing numerous rounded scales, only a few of which 

 carry minute sharp spinelets. Radial shields small, well separated, 

 plainly indicated and made conspicuous by the linear group of spine- 

 lets which they carry, at least on the proximal end. Upper arm 



FIG. 135. OPHIOBYRSA SYNAPTACANTHA. x 4. a, FROM ABOVE; &, FROM BELOW; c, SIDE VIEW OF 



THREE ARM JOINTS NEAR DISK. 



plates separated by naked skin, broken into several pieces, of which 

 two median are largest; none of them carry spines or spinelets. 

 Interbrachial spaces below like disk. Genital slits large. Plates of 

 whole oral surface more or less obscured by skin. Oral shields small, 

 apparently squarish-oval, longer than wide. Adoral plates at sides 

 of shield very small, much longer than wide. Oral papillae and teeth 

 (tooth papillae ?) as in acanthinobrachia. Under arm plates indistinct, 

 apparently longer than wide, with a deep median notch in distal 

 margin. Side arm plates small, each with four cylindrical, blunt, 

 spines, about as long as joint, more or less united to each other by a 

 fold of skin, which includes two-thirds or more of each spine. No 

 tentacle scales. Color (dried from alcohol), dark brown. 



Locality. Albatross station 4933, Eastern Sea, lat. 30 59' N.; 

 long. 130 29' 50" E., 152 fathoms, rocky, bottom temperature 56, 

 1 specimen. 



a luvanrk, signifying joined together, and 8.KavOa, signifying spine, in reference to the 

 webbed arm spines. 



