NORTH AMERICAN LATER TERTIARY AND QUATERNARY BRYOZOA. 
197 
Variations. —Tliis'species, which has been known for a long time, is very common 
in the post-Pliocene formations of California. When the illumination is lateral,the 
segments present a longitudinal and median keel very characteristic. The distance 
between the tubes is smaller than the zooecial width. This character is always 
important to consider in the determination of species of Crisia. 
For reasons of equilibrium there are usually two bases ramae to every segment, 
one on each side. However, it was not rare to find short segments having only one 
basis ramae. 
The number of tubes per segment varies from 11 to 16. 
Affinities. —There is a rather great difference between our photographs and the 
drawings given by Miss Robertson of Crisia pacifica. This difference of aspect is 
due to fossilization; the fossils lose their translucency and the tubes are then scarcely 
visible. 
This species has the general aspect of Crisia denticulata, but differs from it in its 
larger micrometric dimensions, the distance between the peristomes being 0.40 mm. 
and not 0.30 mm. 
Species of Crisia are attached to floating algae. The depth at which they are 
dredged has no bathymetric significance. 
Occurrence. —Pleistocene: Santa Barbara (very common), and Santa Monica 
(very common), California. 
Habitat. —-Pacific: Off California (24-48 meters). 
Plesiotypes. —Cat. Nos. 68735, 68736, U.S.N.M. 
Family TUBULIPORIDAE Johnston, 1838. 
Genus TUBULIPORA Lamarck, 1816. 
(For description see Bulletin 106, U. S. National Museum, p. 753.) 
TUBULIPORA FASCICULIFERA Hincks, 1884. 
Plate 42, figs. 9-17. 
1884. Tubulipora fascieulifera Hincks, Report on the Polyzoa of Queen Charlotte Islands, Annals 
and Magazine of Natural History, ser. 5, vol. 13, p. 206, pi. 9, fig. 6. 
Measurements. —Diameter of the peristome, 0.12 mm. 
Variations. —The fascicles are monoserial or biserial, very short, and composed 
of two to six tubes or more. The zoarium is generally flabelliform, more or less 
elongate: it creeps over algae. The ovicell is small, ramified between some fas¬ 
cicles only. The oeciostome is wide and little salient. 
Affinities. —This species differs from Tubulipora tuba Gabb and Horn, 1862, in 
its very short fascicles, never composed of more than six tubes, and in its wide and 
little salient oeciostome. 
Occurrence. —Pleistocene: Santa Barbara, California (rare). 
Habitat. —Pacific: Off Queen Charlotte Islands. 
Plesiotypes. —Cat. No. 68737, U.S.N.M. 
