ABT. 22. CYCLOSTOMATOUS BRYOZOA CANU AND BASSLER. 115 



sections. A simple, longitudinal section causes two thick lateral 

 walls to appear perforated by the mesopores. This is an optical 

 illusion caused by the relative regularity of the mesopores and the 

 great thickness of their walls. We have called these structures 

 parietal mesopores. 



Pergens, in 1889, observed the identity of the mesopores of Spard- 

 cavea with those of Heteropora and classified all the species in the 

 latter genus. He found it necessary since to separate them, because 

 in Sparsicavea the tubes are club shaped. 



In the form of the ovicell this species must be classified in the 

 Ascosoeciidae. 



Occurrence. — Cretaceous (Upper Turonian or Angoumian) : Ruille- 

 Ponce (Loir-et-Cher), Les Janieres and St. Calais (Sarthe), France 

 (Canu collection). 



Geological distribution. — Turonian and Coniacian of France 

 (Gregory). 



Plesiotifpes.—Q'At. No. 68978, U.S.N.M. 



PARASCOSOECIA MARSSONI Gregory, 1899. 



Plate 19, fig. 11. 



1887. Sparsicavea irregularis Maesson, Die Bryozoen der weissen Schreib- 

 kreide der Insel Riigen, Palaeontologische Abhandlungen, vol. 4, p. 26, 

 pi. 2, fig. 6 (not d'Orbigny). 



1899. Sparsicavea marssoni Gregory, Catalogue of Cretaceous Bryozoa in 

 British Museum, vol. 1, p. 397; 1009, vol. 2. p. 304 (Synonymy). 



We have discovered a superb ovicelled specimen of this species 

 which is figured on plate 19. 



Ocmm'ence. — Cretaceous (Danian) : Herfolge (Seeland), Denmark. 



Geological distribution. — Cretaceous (Campanian) : Island of 

 Riigen, Germany. 



Plesiotijpe.— Cat. No. 68961, U.S.N.M. 



PARASCOSOECIA FRANCQANA D'Orbigny, 1852. 



Plate 19, fig. 12. 



1852. Sparsicavea francqana d'Orbigny, Paleontologie fran(;aise. Terrain 

 Cretace, Bryozoaires. p. 951, pi. 775, figs. 4-6. 



The ovicell of this species measures 1.35 mm. by 0.66 mm. Gregory, 

 1899, was in error in uniting the species with Sparsicavea caran- 

 tina D'Orbigny, 1852, 



Occurrence. — Cretaceous (Danian) : Herfolge (Seeland), Denmark. 



Geological distributioii. — Cretaceous (Senonian) : Departement du 

 Nord, France. 



Plesiotype.—Cdit. No. 68962, U.S.N.M. 



