24 University of California Puhlications in Geology [Vol. 12 



Order Exocycloida Jackson 58 



Suborder Clypeastrina Gregory 58 



Family Clypeast-ridae Agassiz 58 



Genus Clypeaster Lamarck 58 



Clypeaster bowersi Weaver 58 



Clypeaster carrizoensis Kew 59 



Clypeaster deserti Kew 60 



Family Fibularidae Gray 61 



Genus Sismondia Desor 61 



kSismondia (?) arnoldi Twitchell 61 



Sismondia (?) coalingaensis Twitchell 62 



Family Scutellida'- 62 



Genus Scutella Lamarck 62 



Scutella. andersoni Twitchell 62 



Scutella blancoensis Kew 64 



Scutella coosensis Kew 65 



Scutella fairbanksi Arnold 66 



Scutella fairbanksi var. santanensis Kew 68 



Scutella gabbi (Remond) 69 



Scutella gabbi var. tenuis Kew 71 



Scutella merriami (F. M. Anderson) 72 



Scutella newcombei Kew 73 



Scutella norrisi Pack 75 



Scutella tejonensis Kew 76 



Scutella vaquerosensis Kew 77 



Genus Astrodapsis Conrad 78 



Astrodapsis altus Kew 80 



Astrodapsis antiselli Conrad 81 



Astrodapsis arnoldi arnoldi (Pack) 83 



Astrodapsis arnoldi var. depressus Kew 85 



Astrodapsis arnoldi cra.ssus Kew 85 



Astrodapsis arnoldi fresnoensis Kew 87 



Astrodapsis arnoldi peltoides (Anderson and Martin) 88 



Astrodapsis arnoldi spatiosus Kew 89 



Astrodapsis brewerianus (Remond) 91 



Astrodapsis brewerianus var. diabloensis Kew 92 



Astrodapsis californicus Kew 93 



Astrodapsis cierboensis (Kew) 94 



Astrodapsis coahngaensis Kew 96 



Astrodapsis cuyamanus Kew 97 



Astrodapsis fernandoensis Pack 98 



Astrodapsis grandis Kew 100 



Astrodapsis jacalitosensis Arnold 101 



Astrodapsis major (Kew) 102 



Astrodapsis margaritanus Kew 103 



Astrodapsis ornatus Kew < 105 



Astrodapsis (?) pabloensis (Kew) 106 



Astrodapsis scutelliformis Kew 107 



Astrodapsis tumidus Remond 108 



Astrodapsis whitneyi Remond Ill 



Genus Dendraster Agassiz 113 



Dendraster arnoldi Twitchell 113 



Dendrastei ashleyi (Arnold) 115 



