ART. 22. GYCLOSTOMATOUS BRYOZOA CANU AND BASSLER. 63 



The meridian section figured by Gregory indicates the habitual 

 lozenge-shaped areas of the dorsal gemmation. 



Affinities. — This species differs from Homoeosolen ramulosus Lons- 

 dale, 1850, in the presence of its symmetrically arranged pinnules. 



It differs from the species of Truncatula with which Canu has con- 

 fused it in the absence of nematopores and in the presence of the 

 apertures over the entire zoarial surface and not at the extremity of 

 the pinnules alone. 



Occurrence. — Cretaceous (Turonian) : Connere, Dunneau, and St. 

 Calais (Sarthe), France. 



Cretaceous (Coniacian) : Villedieu and Lisle (Loir-et-Cher) and 

 Les Phellipeaux (Charente), France. 



Plesiotypes. — Canu collection and Cat. No. 68986, U.S.N.M. 



Genus TRUNCATULA Hagenow. 1851. 



1S51. Truncatula Hagenow, Die Bryozoen des Maastrichter Kriedebildung, 

 p. 34. 



The ovicell is placed on the dorsal, laterally and between two 

 pinnules. The tubes are cylindrical, oriented, with dorsal gemma- 

 tion; the apertures are elongated, oblique, without peristomes, 

 grouped at the extremity of the pinnules and turned frcm the side 

 of the dorsal. The nematopores are numerous, long, with thick 

 walls, they are often closed by a calcareous pellicle; their ensemble 

 forms a thick wall on the zoarium. 



Genotype. — Truncatula iUix Hagenow, 1851. 



Range. — Cenomanian-Maastrichtian. 



Historical. — D'Orbigny, 1852, has noted that Hagenow's Trwn- 

 culata in most instances corresponds exactly to his O sculipora, but, 

 noting that Truncatula fHx was not an Osculipora^ he maintained 

 Hagenow's genus of which this species ought to be the genotype; 

 unfortunately it is rare and has not yet been the object of special 

 studies. 



Gregory, 1909, confusing the orifices of the nematopores with those 

 of the tubes, classified the species of this genus in Homoeosolen Lons- 

 dale, 1850. The considerable difference between the sections does not 

 permit this conclusion. Evidently the exterior appearance is very 

 deceiving, the orifices of the nematopores being hardly different from 

 those of the tubes; but the well preserved specimens shows the nema- 

 topores closed b}^ a calcareous pellicle, and the longitudinal sections 

 reveal nematopores which do not exist in Homoeosolen. 



Affinities. — This genus differs from Homoeosolen Lonsdale, 1850, 

 in the presence of nematopores, in the occurrence of apertures only 

 at the extremity of the pinnules, and in its ovicells placed on the 



