208 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 8 



nating in blunt points, and the regenerating ray was distinct from the 

 older portion. 



The short, robust, nontapering blunt arms, 2 regular series of margi- 

 nal plates, 2 regular series of lateral papular areas, and the very broad 

 abactinal area distinguish this species from other members of the family 

 Linckiidae in the eastern tropical Pacific. 



The type locality was again visited by the Velero III in 1935 and 

 1938 in the hope of collecting additional specimens of this unique species, 

 but none were obtained. 



The name mionactis (less-ray) refers to the rays that are shorter 

 than usual. 



Genus TAMARIA Gray 



Tamaria obstipa, new species 

 Plate 33, Figs. 1-2; Plate 34, Fig. 1. 



Description. — Rays 5, R=36 mm., r=7 mm., R=5 r. Rays slender 

 and tapering; width at base 8 mm., midray 6 mm., ray tip 3.5 mm. Disk 

 slightly convex, plates swollen, to one side of the central plate is the anal 

 aperture. The plates of ray are disposed in the following series: at base of 

 ray, 3 abactinal, 4 marginal, 6 actinal in addition to a series of secondary 

 intermarginals ; at middle of ray, 2 actinal series less ; near tip of ray, 1 

 abactinal (carinal), 4 marginal, actinal. All of the plates are covered 

 with closely compacted, rounded or polygonal granules ; those on the con- 

 vex surface of the plates are larger than those in the depressed areas be- 

 tween the plates. There is no definite arrangement of the granules, except 

 in the depressions between the plates where single, transverse rows often 

 mark the margins of the plates, leaving between them a noticeable trans- 

 verse furrow, especially distinct in the abactinal and marginal series. 



The papular areas are arranged in 6 rows; 4 abactinal series extend 

 two thirds of the ray; they are not continuous; often there are 2 or 3 

 plates in succession without papular areas. Intermarginal series regular, 

 reaching within a few plates of ray tips. Papulae in each area vary from 

 6 to 24, distally some areas had as few as 3. There are no papular areas 

 on the actinal surface. 



The adambulacral plates about three times as broad as long, about 3 

 plates opposing 2 of the adjoining series. Each plate bears a large sub- 

 ambulacral and 2 smaller furrow spines in addition to numerous enlarged 

 granules. The adambulacral armature consists of 2 distinct rows of spines, 

 set close together; those on the furrow are small, flat, blunt, chisellike, 



