NORTH AMERICAN EARLY TERTIARY BRYOZOA. 
181 
The zooecia have large opesia. A gymnoevst and a cryptocyst are more or 
less developed. The mural rim bears distally one or two pairs of spines and 
laterally a membranous scutum. The distal wall, consisting of a horizontal, basal, 
and an obliquely ascending frontal part, has usually numerous small, scattered, 
uniporous septulae basally, while the distal half of each lateral wall has one 
multiporous septula. Besides dependent avicularia, found in most species, vibracula 
may also occur on the basal surface of the zoarium, and these are connected with 
the zoarium by an independent wall. The ovicells are generally hyperstomial. 
As a rule radicular fibers occur, sometimes springing from a septula (or a dietella), 
sometimes from a separate chamber connected with a vibraculum. The zoaria are 
always free, very branched, most frequently with uni- or few-seried zooecia, gen- 
erally consisting of a single layer and in most cases jointed by means of chitinous 
transverse belts. (After Levinsen, 1909). 
Figure 49 gives a summary of the most important anatomical features in this 
family. No trace of the scutum is left on the fossil forms, but its presence is 
revealed by a small pore situated on the mural rim. American Tertiary specimens 
are rare, small, and very fragile, and as a result we have been unable to make any 
detailed studies of the family. 
The principal genera of this family are : 
Cqberea Lamouroux, 1816. 
CaberieTla Levinsen, 1909. 
Canda Lamouroux, 1816. 
Scrupocellaria Van Beneden, 1844. 
Bugulopsis Verril, 1879. 
Iloplitella Levinsen, 1909. 
Rhabdozoum Hincks, 1882. 
Menipea Lamouroux, 1816. 
The two genera Gaberea and Scrupocellaria alone are represented in the Ameri- 
can collections studied. Canda, and Scrupocellaria are very similar. Levinsen 
distinguishes those genera by their ovicells and Waters by their articulation. 
Genus SCRUPOCELLARIA Van Beneden, 1844. 
1S44. Scrupocellaria Van Beneden, Reclierehes snr l’organisation des Laguncula et 1'his- 
toire naturelle des differents Polypes Bryozoaires, Nouveaux Memoires de l'Academie 
Royal e de Bruxelles, vol. IS, p. 44. 
Zoarium jointed. Zooecia numerous in each internode, rhomboid; opesia with 
or without scutum; a sessile avicularium at the upper, outer, lateral angle, a vibrac- 
ulum at the lower outer angle, and generally a sessile avicularium on the front sur- 
face of each zooecium. (Robertson.) 
Accepted, genotype. — Scrupocellana scruposa Linnaeus, 1758. 
Range. — Lutetian-Recent. 
