136 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I44 



GENERIC DESCRIPTION 



Small, low, broad, flat adoral surface ; apical system tetrabasal, 

 with genital pores in normal position in genital plates ; petals long, 

 broad, equal, closing distally ; ambulacral plates beyond petals single 

 pored ; periproct marginal, small, longitudinal ; peristome anterior, 

 circular with height equal to width; bourrelets strongly developed, 

 toothlike, phyllodes broad, single pored, few pores arranged in two 

 series in each half -ambulacrum, pores widely separated from peri- 

 stome ; buccal pores on edge of peristome. 



Comparison with other genera. — Lambert and Thiery (1921, p. 

 363) considered Lefortia a subgenus of Procassidulus. L. delgadoi 

 resembles the type species of Procassidulus (=Rhynchopygus) , R. 

 lapiscancri (Leske), in having a flattened adoral surface, well- 

 developed bourrelets, broad, single-pored phyllodes, and a tetrabasal 

 apical system. It differs from R. lapiscancri in having a marginal 

 instead of supramarginal periproct, a larger test, and more pro- 

 nounced petals. 



Lefortia resembles Eurypetalum but dififers in having a marginal, 

 longitudinal periproct as opposed to an inframarginal, transverse 

 periproct. Faujasia differs from Lefortia in having its genital pores 

 in the interambulacra, monobasal apical system, and an inframarginal, 

 transverse periproct. In Domechinus the apical system is monobasal, 

 and the periproct transverse rather than longitudinal. 



Remarks. — Cooke (1953, p. 17) described a new species of 

 Lefortia, L. trojana, from the Maestrichtian of Mississippi. This 

 species is very similar to the type species, L. delgadoi, and is with- 

 out doubt congeneric. Cooke described its apical system as being 

 monobasal, but I have cleaned the type specimen and found plate 

 sutures around the genital plates showing it to be tetrabasal. 



Range and distribution. — Cretaceous (Senonian) of Europe, India, 

 Madagascar, and America. 



DESCRIPTION OF TYPE SPECIES 



LEFORTIA DELGADOI (De Loriol) 



Plate 18, figures 9-12; text figures 115, 116 



Pomelia delgadoi De Loriol, 1900. Rev. Suisse Zool., vol. 8, p. 67, pi. 6, 

 figs. 6-8. 



Material. — De Loriol's four cotypes were studied. The specimen 

 he figured in his plate 6, figure 6, is herein designated the lectotype. 



