Polyzoa and Anthozoa from Upper Cretaceous Limestone. 7 



subgenus of Crisina, from which it differs in possessing a simple 

 median series of apertures on the obverse face. The fact that it is 

 not always easy to distinguish this series as composed of apertures 

 distinct from the most median apertures of the lateral series shows 

 the artificiality of the genus. This point is well exemplified in von 

 Hagenow's figure of T. dorsata (von Hagenow). 



TERVIA DORSATA (von Hagenow). 

 Plate I., fig. 8. 



1851. Idmonea dorsata,von. Hagenow, Bry. Maastr. kr., p. 31, pi. ii., 

 fig. 10. 



Zoarium subcylindrical or triangular or flattened in a plane parallel 

 to the obverse and reverse faces ; without dorsal processes ; reverse 

 face flat or concave ; zocecia three or four in a lateral series, im- 

 mersed but the boundaries are clearly marked; the distance between 

 the different series of apertures is one and a half to two and a half 

 times the diameter of an aperture ; those of the same series are 

 distant about a quarter the diameter of an aperture. This is the 

 commonest form among the specimens of Cyclostomes from Need's 

 Camp. 



Distribution. Senonian. 



TERVIA GIBBERA, Gregory. 

 Plate I., fig. 9. 



1899. Crisina (Tervia) gibbera, Gregory, Brit. Mus. Cat. Cret. Bry., 

 vol. i., pp. 173-4, Text fig. 12. 



Zoarium subcylindrical with the reverse face flat and possessing 

 spine-like projections, bearing no zocecia, termed by Gregory " dorsal 

 processes"; zooecia about three in a lateral series, immersed, but 

 the boundaries are just shown ; distance between the different series 

 of apertures three to four times the diameter of an aperture ; those 

 of the same series distant about one-half the diameter of an 

 aperture. Only two specimens have been found among the material 

 here described. 



Distribution. Senonian. 



TERVIA DECURRENS (Pocta). 



1892. Idmonea decurrens, Pocta, Mech. koryc. Hory. ; Ceska. Ak. Fr. 

 Jos. Pratze, sect. 2, p. 18, pi. ii., figs. 3-6. 



Zoarium subtriangular in cross-section and flat on the reverse side ; 

 the zocecia are immersed with their boundaries apparent ; apertures 



