NORTH AMERICAN LATER TERTIARY AND QUATERNARY BRYOZOA. 197 



Variations.— This 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 

 beUveen 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 ramac 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 

 drawmgs given by Miss Robertson of Crisia facifica. 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 m 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. 



Occwrre/ice.— Pleistocene: Santa Barbara (very common), and Santa Monica 

 (very common) , California. 



Habitat.— FaciRc: Off California (24-48 meters). 



Plesiotypes.— Cat. Nos. 6873-5, 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 Hlncks, 1884. 



Plate 42, figs. 9-17. 



1884. Tubuliporafaseiculifera Hincks, Report on the Polyzoa of Queen Charlotte Islands, Annals 

 and Magazine of Natural Histor)-, ser. 5, vol. 13, p. 206, pi. 9, fig. 6. 



il/easMremen^s.— 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 Tuhulipora 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.— Fixci&c: Off Queen Charlotte Islands. 



Plesiotypes.— Cat. No. 6S737, U.S.X.M. 



