ASTEROIDEA 123 



are 4 or 5 coarse granules in 2 longiseries. The aboral granule of inner series is often en- 

 larged into a tubercle one-half or two-thirds length of furrow spine. In the paratype this 

 tubercle is present on nearly all the plates, is thicker than furrow spines, and increases in 

 length so that on ray proper it is as long as and much heavier than the furrow spines. In 

 the type its occurrence is very irregular. 



The combined mouth-plates are lozenge-shaped actinally, the furrow margin being 

 about as long as the first adambulacral suture. Marginal spines 4 or 5, similar to proximal 

 adambulacral furrow spines but a little longer and gradually lengthening to the oral 

 angle where the 2 " teeth " are the longest spines on the body. Each plate normally has 

 one suboral adjacent to distal marginal spine while the outer half of combined plates is 

 covered with low coarse granules. 



Type locality. St. 170. Off Cape Bowles, Clarence Island, 342 m., rock, 

 2 specimens. 



Remarks. This species differs from P. incertus as indicated in the diagnosis. In all the 

 specimens of P. tessellatiis Koehler, of which the largest has R 43 mm., the midradial 

 series of abactinal plates reaches the terminal plate, thereby separating the distal 

 superomarginals ; while the adjacent adradials reach the ninth or tenth superomarginals, 

 which is farther than the radial series reaches in P. synaptorus. In the much smaller 

 type of incertus the adradials reach to the sixth superomarginal (i i in all) or to about one- 

 third R from end of ray. In P. synaptorus the adradials extend along ray two-fifths R 

 (or to three-fifths R from end of ray). 



Genus Cladaster Verrill 



Cladaster analogus sp.nov. 



(Fig. D, 2; Plate IV, figs. 1-3) 



Diagnosis. Closely related to Cladaster validus Fisher; stellato-pentagonal with 

 short rays, thick disk, block-like marginals and unequal, spaced granulation on surface of 

 plates ; madreporite larger than any abactinal plate ; pedicellariae very broadly spatulate 

 with flat jaws, arising from a pit on the plate but without a differentiated depression for 

 the opened jaws; superomarginals 11; adambulacrals with 2, sometimes 3, heavy, 

 compressed round-tipped furrow spines; one major subambulacral and a secondary 

 smaller one on outer end of plate independent of the small marginal granules. R 57 mm., 

 r 34 mm., br (interradius) 35-37 mm. 



Description. The abactinal plates are fairly regularly arranged on the radial areas in 

 series parallel to the midradial, in which the largest plates are situated about one-third 

 R from the conspicuous subcircular central plate. Across the ray from interradius to 

 interradius and passing the midradial series at about mid R are 13 plates. The radial 

 plates are subcircular to subhexagonal, the others mostly subcircular. They are separated 

 by a shallow furrow covered normally by the close-set, peripheral granules which are 

 superficially 4-sided, round-tipped, convex, and deciduous. The exposed surface really 

 constitutes a very low tabulum and is nearly plane. It normally carries, spaced unequal. 



