40 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 8 



Interbrachial spaces below covered by the large oral shield surrounded 

 by a few smaller plates. In the interbrachial area is a large plate in con- 

 tact with the oral shield and the upper interradial plate. First under arm 

 plate large, slightly longer than wide, with a convex proximal margin and 

 concave distal margin, widely separated from the 2nd under arm plate 

 by a groove. Second plate rectangular, 3rd and succeeding plates longer 

 than broad, becoming diamond shaped distally, reduced in size and far- 

 ther separated by the side arm plates, which meet below between the 4th 

 and 5th under arm plates. The first 5 arm plates are separated below by a 

 deep groove. Plates swollen and deeply pitted. Genital slits large, extend- 

 ing from the radial shields to the adoral plates. Thirteen to 18 spines on 

 the genital ridge, those above long, blunt, and well spaced, undermost 

 become shorter, broader, flatter, and compacted. Three broad, flat ten- 

 tacle scales, outermost largest on 1st under plate. Two broad, flat ten- 

 tacle scales on the adoral plate. Three flat, broad tentacle scales on the 

 2nd and 3rd under plates. Three broad flat tentacle scales on the 1st and 

 2nd side arm plates. Two tentacle scales on the next 3 under arm plates 

 and then only one for 3 plates before disappearing. Two tentacle scales on 

 the 3rd to 5th side arm plate and then only one to the end of the arm. 



Color. — Dried from alcohol, white with a lavender tinge, stained 

 brownish drab about the base of the arms. 



Types. — Holotype, AHF no. 8; 13 paratypes, 5 in M.C.Z. 

 Type locality.— ^t?iX.\on 818-38, 300 fms., south of Hood Island, 

 Galapagos, January 20, 1938. Thirteen additional parat^Tes, 5 in the 

 Museum of Comparative Zoology, from Station 786-38, 392 fms., N.E. 

 of Indefatigable Island, Galapagos, January 18, 1938. 



Remarks. — The thick rounded disk, short rapidly tapering arms, sym- 

 metrical disk rosette, and unique deep pits on the primaiy plates, espe- 

 cially the basal upper arm plates, which resemble the mesh on a golf ball, 

 easily distinguish the adults of this species from other known members of 

 the genus. Unfortunately, in small specimens the pitted surface is not 

 noticeable under an ordinary lens but requires a magnification of 40 

 diameters or more. It approaches Stegophiura in the shape of the arms, 

 but the disk scales and arm spines are more like Amphiophiura. This 

 species has been named paucisquama in reference to the small number of 

 disk plates. 



