NO. 3 CASSIDULOID ECHINOIDS — KIER I25 



DESCRIPTION OF TYPE SPECIES 



PETALOBRISSUS SETIFENSIS (Cotteau) 

 Plate 16, figure 10-13; text figures 108, 109 



Echinobrissus setifensis Cotteau, 1866. Rev. Mag. Zool., ser. 2, vol. 18, 

 pp. 267-268, pi. 14, figs. 13-15- 



Material — I studied six specimens in the Museum National d'His- 

 toire Naturelle, Paris, and one in the U. S. National Museum. 



Shape. — Small, 20 to 30 mm. long, elongate, subangular in mar- 

 ginal outline, greatest width posterior to center, greatest height an- 

 terior; adapical surface inflated, with posterior slightly truncated 

 obliquely; adoral surface flat to slightly pulvinate. 



Apical system. — Anterior, tetrabasal, four genital pores (text fig. 

 108), posterior genital plates not in contact. 



Ambulacra. — Petals well developed, broad, lanceolate equal, closing 

 distally ; poriferous and interporiferous zones tapering distally ; pores 

 conjugate, outer pore elongated transversely, inner round. 



Periproct. — On lower edge of slight oblique, posterior truncation, 

 supramarginal with opening slightly visible from above, longitudinal. 



Peristome. — Anterior, wider than high, pentagonal. 



Floscelle. — Bourrelets strongly developed, inflated, projecting into 

 peristome; phyllodes (text fig. 109) broad, single pored with two 

 series of pores in each half ambulacrum : 10 to 12 pores in each outer 

 series, 4 or 5 in each inner ; buccal pores present. 



Occurrence. — Upper Cretaceous (Maestrichtian) of Dra-Toumi, 

 Kef Matrek, south of Medjes, Mahdid, Djebel Mzeita, Department 

 of Constantine, Algeria. 



Location of type specimen. — According to Cotteau (1866, p. 268) 

 the type specimen is in the Coquand Collection. I do not know where 

 this collection is. 



Genus STIGMATOPYGUS d'Orbigny 



Stigmatopygus d'Orbigny, 1856. Pal. franc, Cretace, vol. 6, p. 331. Type 

 species, Stigmatopygus galeatus d'Orbigny by subsequent designation, Lambert 

 and Thiery (1921, p. 363). 



GENERIC DESCRIPTION 



Medium to large size, elongate to broad, inflated adapical surface, 

 flattened adoral ; apical system tetrabasal, petals broad, equal, closed, 

 conjugate pores, ambulacral plates beyond petals single pored; peri- 

 proct supramarginal, longitudinal, high on oblique posterior trunca- 



