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University of California Puhlioatiom in Geology [Vol. 12 



odd anterior ambulacral area ; margin slightly thicker in the anterior 

 part. Apical system anteriorly eccentric to a slight degree. Upper 

 surface much depressed ; rises gradually to a low apex, which is 

 anterior to the apical system. Ambulacral area nearly twice the width 

 of the interambulacra at the ambitus ; ambulacra petaloid. Lateral 

 petals subelliptical in outline ; angle between the axes of the anterior 

 lateral petals is nearly 180°. Inner rows of pores diverge gradually 

 for about two-thirds the length of the petal and then converge slightly 

 to the end. Outer rows diverge somewhat more at first and converge 

 to a greater degree in the distal end. This arrangement of pores 

 gives the petals an appearance of having a slight tendency to be 

 closed at their extremities. Each poriferous area about one-half the 

 width of the interporiferous area. Odd anterior petal wider than 

 the others, due to the greater width of the interporiferous area ; inner 

 rows of pores in this petal diverge to the end ; outer rows converge 

 slightly in the distal part. This arrangement gives the petal a wide 

 open, or flaring appearance. All petals extend about two-thirds the 

 distance to the margin. Inferior surface flat, with ambulacral furrows 

 extending from the peristome to the margin, and in the specimen ex- 

 amined appear to be simple and undivided. Peristome central, rather 

 large, and round. Periproct small, inframarginal, and situated about 

 midway from the posterior margin to the mouth. Tubercles on the 

 upper surface small and crowded ; those on the inferior surface some- 

 what larger, and placed in distinct serobicules. 



Related forms. — This form seems to be closely related to Scutella 

 hlancoensis Kew, but differs in that it is considerably larger and does 

 not possess the angular posterior margin ; the petals do not extend 

 so near to the margin ; the angle between the two anterior lateral petals 

 is greater, the axes of the two forming an approximately straight 

 line ; the anterior margin in the odd ambulacral area is truncated ; 

 and the poriferous areas of the petals are somewhat narrower. It 

 also resembles *S'. gabbi (Remond), large form, but may easily be dis- 

 tinguished by its larger size, and the truncation of the margin in the 

 anterior ambulacral area. In this latter character it is like S. fair- 

 hanksi Arnold, but differs from this species in having wider and much 

 longer petals which are flush with the surface of the test, whereas on 

 8. fairbanksi they have a slight tendency to be raised. 



Geologic horizon. — Sooke beds, Oligocene? 



Localities. — Holotype from Slide Hill Beach, Vancouver Island, 

 British Columbia, Leland Stanford Jr. Univ. Dept. Geol. loc, N. P. 

 131. 



