NO- 3 CASSIDULOm ECHINOIDS — KIER ^J 



Comparison with other gcnera.—PscudosorcIla is very distinct 

 from any other genus. Its phyllodes and position of periproct are 

 similar to those of Nucleolites, but its shape and its petals easily 

 distinguish it. Its periproct is similar to Clypeus, but its petals are 

 very different, having very narrow poriferous zones, and its test is 

 much higher. 



Range and distribution. — Jurassic (Rauracian) of France, Switzer- 

 land, and Syria. The age of the Syrian species is not certain but is 

 presumed to be Rauracian. 



DESCRIPTION OF TYPE SPECIES 



PSEUDOSORELLA ORBIGNYANA (Cotteau) 



Plate 9, figure 13; plate 10, figures i, 2; text figure 50 



Desoria orhignyana Cotteau, 1855. £ch. foss., L'Yonne, vol. i, p. 227, pi. 33, 

 figs. 9-1 1. 



Material. — One specimen studied in the Museum National d'His- 

 toire Naturelle and a second in the ficole National Superieure des 

 Mines in Paris. This latter specimen is Cotteau's (1872, pi. 84, Pal. 

 franc, Jur.) figured specimen. 



Shape. — Medium size, very broad, inflated with rounded margin, 

 greatest height posterior to center; adorally, ambulacra depressed, 

 interambulacra inflated. 



Apical system. — Central, tetrabasal. 



Ambulacra. — Petals broad, long, almost extending to ambitus ; 

 open ; paired petals straight or with distal portions slightly curved 

 posteriorly; interporiferous zones very wide, poriferous zones nar- 

 row; with width of poriferous zones decreasing distally; pores 

 strongly conjugate, outer pore slitlike, inner pore round. 



Figs. 50-57. — 50, Pseudosorella orhignyana (Cotteau) : Phyllode of ambu- 

 lacrum II from specimen in Museum National d'Histoire Naturelle, Paris, from 

 the Corallian at Valfin (Jura), France, X 7- 5i> Pseudosorella syriaca (De 

 Loriol) : Phyllode from ambulacrum V of lectotype in Museum d'Histoire Na- 

 turelle, Geneve, Switzerland, from the Jurassic at Mar-Abda at the bottom 

 of the Ghazir Valley, Syria, X IS- 52, Clypeopygus paultrei (Cotteau) : Phyl- 

 lode of ambulacrum II of specimen in Lambert Collection, Sorbonne, Paris, from 

 the Lower Cretaceous (Neocomian), at Marolles, X 10. 53, Catopygus fenestra- 

 tus Agassiz : Phyllode of ambulacrum I of USNM 131271, from Upper Creta- 

 ceous (Maestrichtian) at Ciply (near Mons), Lienard Quarry, Belgium, X I5- 

 54, Catopygus mississippiensis Cooke: Phyllode of ambulacrum I of holotype, 

 USNM 108379, from Upper Cretaceous (Maestrichtian), from bed of a branch 

 stream near Mobile and Ohio Railroad tracks about 5 miles northeast of Houston, 

 Miss. 55-57. Catopygus carinatus (Goldfuss) : 55, Phyllode of ambulacrum V 

 of USNM 131277, from the Cretaceous (Cenomanian) at Saint Didier des Bois 

 (Eure), France, Xi5; 56, apical system of same specimen, X20; 57, adoral 

 view of interambulacra 4, 5, showing plate arrangement of same, X 3- 



