184 BULLETIN 100, UNITED STATES NATIONAL MUSEUM 



Genus LEVINSENELLA Harmer, 1926 



(Columnaria Levinsen, 1909; preoccupied) 



The ovicells are strongly prominent. The zooecia are without 

 spinous processes; the distal wall has a number of scattered uni- 

 porous septulae. The avicularia are capitate, attached to the distal 

 wall at their proximal part and firmly fixed with their basal wall to 

 the frontal membrane of the distal zooecium. The colonies are not 

 jointed. (Levinsen, 1909.) 



Genotype. — Columnaria borealis Levinsen, 1909. Recent. 



Genus FARCIMINARIA Busk, 1852 



"The ovicells are surrounded by kenozooecia. The zooecia have 

 a larger or smaller number of small, spinelike processes, which are 

 placed either on the frontal membrane or on the lateral margins; the 



Fig. 56. — Genus Didymozoum Harmer, 1923 (Didymia Busk, 1852) 



A-D. Didymozoum simplex Busk, 1852. A. The zoarium, natural size. B. 

 Anterior side of a fragment. The zooecia are placed on the same plane and open 

 on the anterior face. C. The ovicelled zooecia are located between two zooecia 

 in a bifurcation. (A-C. After Busk, 1852.) D. Lateral wall, showing uni- 

 porous septulae, X85. (After Waters, 1887.) 



colonies are chitinous and are not jointed" (Levinsen, 1909). Num- 

 erous chitinous radicells twisted on the length fix the zoarium in the 

 sand (Jullien, 1903). 



Genotype. — Farciminaria atlantica Busk, 1884. Recent. 



Genus DIDYMOZOUM Harmer, 1923 



Special method of bifurcation (type .1 of Harmer). The zoaria 

 are biserial. The ovicell-bearing zooecia placed between two zooecia 

 in a bifurcation. No scptules between two neighboring zooecia. 



Genotype. — Didymozoum (Didymia) simplex Busk, 1852. Recent. 



