PROCEEDINGS OF THE NATIONAL MUSEUM 



voti. 66 



moderate breadth, reaching to within a short distance of the ambitus, the un- 

 paired and anterior paired petals being straight, the posterior paired ones 

 sliglitly sinuous; breadth of a pore belt (apparently) about half that of a 

 semiambulaorum, the part of the ambulacrum between the pore belts orna- 

 mented with light-colored puncta (the supposed spine scars) arranged in quin- 

 cunx ; interambulacral plates thick, separated by deep sutures that are made 

 especially pronounced by the beveled borders of the plates, the adambulacral 

 half (on distal plates, less than half) of each plate being crossed with slightly 

 raised, parallel curved lines, which subtend the borders of the ambulacral 

 petals and between which are puncta that, like those of the ambulacral mid- 

 areas, present the appearance of filled pores and are in quincunx, though form- 

 ing a simple linear series between each two lines ; surface of inner, or con- 

 tiguous, halves of interambulacral plates plain (or at least without lines, and 



Fig. 1.- 



-Hypothetical Rbstoeation of Scutellaster Ceetaceus Cragin, Based on thh 

 Type and a Miocene Scctblla 



with only minute puncta, which, in the type specimen, are mainly obliterated), 

 save near the ends, where a number of coarse puncta are so arranged as to 

 constitute a narrow and indefinitely bounded miliary zone. 



Between the anterior and either antero-lateral angle, the outline of the test, 

 as viewed from above, presents two trifling concavities separated by a broader 

 convexity. Between either antero-lateral angle and the posterior angle of the 

 same side, the outline presents a broad and shallow concavity which culminates 

 opposite the anterior part of the posterior row of plates of that interambulacral 

 field. The bottom of the test is not shown in the type, and the posterior border 

 is imperfect, so that the exact form of the latter and the exact position, etc., 

 of the peristome and periproct are unknown. 



Measurements. — Length of test, 10.'); breadtli, 83; height (approximately), 



8-10 mm. 



