154 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I44 



being tetrabasal with genital 2 also extending posteriorly. Szorenyi 

 (1955b, text fig. 5) shows a monobasal apical system in her Archiacia 

 hnngarica, but I suspect that her figure is inaccurate. The shape of 

 the genital plates and the location of the madreporic pores suggests 

 a tetrabasal system. 



The floscelle is very similar in most of the species of Archiacia. 

 As the phyllodes have not been figured before in this genus, I include 

 a drawing of a phyllode of A. palmata (text fig. 126) and A. saaden- 

 sis Pcron and Gauthier (text fig. 127), and photographs (pi. 22, 

 figs. 7-9) of ^. palmata. 



Szorenyi (1955a, text fig. 6) shows single pores in ambulacrum III 

 of Archiacia hnngarica. As all the specimens of Archiacia that I 

 have seen have the pores paired, I suspect that her drawing is incor- 

 rect and that they are pore pairs. 



Ecology. — Szorenyi (1955b, pp. 383-384) suggested that the high 

 test of echinoids of this genus, with the petals near the apex, indicate 

 that they lived partially buried on the sea floor. 



Range and distribution. — Cretaceous (Cenomanian) of the circum- 

 Mediterranean countries; Szorenyi (1955a) has described two species 

 from the Lower Cretaceous (Urgonian to Aptian) of Bakony. 



DESCRIPTION OF TYPE SPECIES 



ARCHIACIA SANDALINA L. Agassiz 



Plate 22, figures 4-6 



Archiacia sandalina L. Agassiz, in Agassiz and Desor, 1847. Ann. Sci. Nat., 

 ser. 3, vol. 7, p. 159; figured in Ann. Sci. Nat., ser. 3, vol. 6 (1846), pi. 15, 

 figs. 24-26, not figs. 27, 28 as stated by Agassiz. Although this species was 

 figured by Agassiz in 1846, there was no plate explanation and the species 

 must date from his description. Many authors have attributed this species 

 to d'Archiac. However, the manuscript in which he referred to this name 

 was never published. 



Material. — I studied one specimen in the d'Orbigny Collection in 

 the Museum National d'Histoire Naturelle. This is evidently the 

 specimen referred to by d'Orbigny (1856, p. 285) but not the speci- 

 men he figured. The specimen is fairly well preserved, although part 

 of the apical system and peristome is absent. 



Shape. — Medium size (approximately 30 mm. in length), elongate, 

 with adapical surface strongly inflated anteriorly, with pointed promi- 

 nence overhanging anterior margin; adorally margin flat, but de- 

 pressed around peristome. 



