46 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I44 



almost to margin, petals II and IV two-thirds to margin, petals V 

 and I between one-half and two-thirds distance to margin; inter- 

 poriferous zones very wide, tapering distally; poriferous zones wide 

 with outer pore slitlike, inner pore slightly elongated transversely, 

 pores conjugate, 



Pcriproct. — Inframarginal, longitudinal with anterior side of open- 

 ing slightly pointing, posterior blunt ; in slight, flat groove extending 

 one-third distance from periproct to peristome. 



Peristome. — Anterior, pentagonal, width slightly less than height. 



Floscelle. — Not exposed on any specimens studied by this author, 

 with following description based on illustrations by d'Orbigny ( 1856, 

 pi. 917, figs. I, 4) and Cotteau (i860 [1857-1878], pi. 59, fig. 6; 

 Yonne). Bourrelets well developed; phyllodes large (chart 3, fig. h), 

 greatly broadened, depressed, with two series of double pores in each 

 half -ambulacrum, approximately 13 pore pairs in each outer series, 

 6 in each inner ; no buccal pores ; pore series terminate at consider- 

 able distance from edge of peristome. 



Occurrence. — Lower Cretaceous (Neocomian) of France and 

 Switzerland. 



Location of type specimen. — According to Lambert and Jeannet 

 (1928, p. 177) the holotype is at the Institut de Geologic at Neucha- 

 tel, Switzerland. 



Synonym of PYGURUS (PYGURUS) 



Echinopygiis d'Orbigny, 1856. Pal. franc, Cretace, vol. 6, p. 303. Type species, 

 Clypeastcr oviformis var. 2 hamarck=Echitioaus lampas De la Beche by 

 subsequent designation, Lambert and Thiery (1921, p. 355). 



DESCRIPTION OF TYPE SPECIES 



PYGURUS (PYGURUS) LAMPAS (De la Beche) 



Plate 3, figures 1-3; chart 3, figure k 



Echinoaus lampas De la Beche, 1833. Trans. Geol. Soc, scr. 2, vol. 1, p. 42, 

 pi. 3, figs. 3-5- 



Material. — Three specimens were studied in the ficole des Mines, 

 Paris. One of these is the specimen figured by De la Beche, according 

 to its label. This specimen is herein designated the lectotype. 



Shape. — Large, lectotype 74.0 mm. long, length greater than width, 

 margin angular with posterior greatly prolonged, adoral surface 

 inflated with greatest height anterior to center at apical system and 

 with steeply sloping sides ; greatest width posterior to center ; adoral 

 surface concave. 



