58 CALIFORNIA ACADEMY OF SCIENCES [Proc. 4th Ser. 



Descriptions of Species 

 Chico (Upper Cretaceous) 



All types and figured specimens are in the Leland Stanford 

 Jr. University Paleontological Collection. 



Cotypes of new species are in the museum of the California 

 Academy of Sciences. 



Locality 1 — Chico area north of the Simi fault (near Ven- 

 tura-Los Angeles county line. 



Locality 2 — Chico area in Bell's Canyon north of Simi fault. 



Locality 3 — Chico area south of the Santa Monica Moun- 

 tains. 



None of these Chico species is known to occur in the Eocene. 



Ophiuroidea 



Amphiura lymani, new species. 



PI. 9, Fig. 13 



A rather detailed impression of this brittle star was ob- 

 tained from the uppermost transitional shales of the Chico 

 formation, Locality 2, L. S. J. U. Pal. Coll. Disc small, 

 diameter 4 mm., pentagonal in outline. Arms short, slightly 

 tapering. Arm spines sharp, and slightly longer than the 

 breadth of the brachial plates. 



This species differs from Amphiura sanctcecrucis Arnold,^" 

 in its smaller size, relatively shorter and less tapering arms, 

 and in the slenderness of the arm spines. The genus to which 

 the species belongs was kindly determined by Mr. Herbert 

 Lyman Clark of Cambridge, Massachusetts, in whose honor 

 the species is named. 



ECHINOIDEA 



Scutella (?) species. 



PI. 9, Fig. 14 



A single fragment of a Scutella (?) was obtained from the 

 upper transitional shales of the Chico formation. The dorsal 

 section figured shows the plates and relative proportions. 



'" Description of a new brittle star from the upper miocene of the Santa Cruz 

 Mountains, Calif. Proc. U. S. Nat. Mus., vol. 34, pp. 403-406, 1908. 



