ABT. 22. CYCLOSTOMATOUS BRYOZOA CANU AND BASSLER, 31 



Occurrence. — Cretaceous (Coniacian) : Tours (Indre-et-Loire), 

 France. 



Cotypes. — Canu collection. 



NOTOPLAGIOECIA FLEXUGSA D'Orbigrny. 1853. 



Plate 5, fig. 5. 

 1853. Laterotubigera flexuosa d'Okbigny, Pal&ontologie fraucaise, Terrain 

 Cr6tac§, vol. 5, p. 715, pi. 754, figs. 2-4. 



A^nities. — In its small dimensions this species is quite close to 

 Mecynoecia micropora D'Orbigny, 1853, but its peristome is always 

 elliptical and transverse. This difference is quite impcutant and 

 moreover the ovicell is of an absolutely different type. In spite of 

 appearances the two species do not belong to the same family. 



The peristome measures 0.14 by 0.20 mm. and the di;, meter of the 

 tubes is 0.20 mm. Almost all the^ peristomes are adjacent to each 

 other. 



It differs from Notoplagloecla {Seymlaterotubigera) annulafa 

 D'Orbigny, 1853, in which the peristome is also transverse in its 

 micrometric dimensions. 



Geologic distribution. — Cretaceous (Turonian) : Angouleme (Cha- 

 rente), France. 



Cretaceous (Coniacian) : Tours (Indre-et-Loire) and Villedieu 

 (Loir-et-Cher), France. 



Cretaceous (Santonian) : Barbezieux (Charente), France. 



NOTOPLAGIOECIA ANNULATA D'Orbigny. 1853. 



1853. Semilaterotubigera annulata d'Orbigny, PalSontologie frangaise, 

 Terrain Cr^tace. vol. 5, p. 750, pi. 762, figs. l.S-15. 



We have not yet discovered the ovicell of this rather common 

 species, which, nevertheless, is easily distinguished by its micrometric 

 dimensions from Mecynoecia micropora D'Orbigny, 1853, and from 

 Notoplagioecia flexuosa D'Orbigny, 1853. This is the largest species 

 of the three ; the transversal diameter of the peristome is from 0.18- 

 0.20 mm. and that of the tubes from 0.26-0.30 mm 



The tubes are bent upward at their extremity and the peristome 

 is slightly oblique. Illuminated from below, the latter appears 

 transverse, but it appears orbicular when lighted from above. This 

 peculiarity is the cause of the disorder which exists in D'Orbigny 's 

 specimen tubes and of his somewhat erroneous figure. 



The zoaria are generally hollow and are terminated at their ex- 

 tremity by a solid part, as has been well figured by Pergens. They 

 are often quite large and attain one centimeter in width. 



One must not confound this species with Laterotuhigera macropora 

 D'Orbigny, 1853, in which the dimensions are much larger (peri- 



