NORTH AMERICAN LATER TERTIARY AND QUATERNARY BRYOZOA. 
49 
This is the sixth species with large spines found at Santa Barbara, California. 
We are ignorant of the true function of these spines, but there is reason to believe 
that their ensemble forms a trap for diatoms the usual food of bryozoa. The very 
calm waters off California, therefore, obliged these animals to multiply their means 
of capture. 
Occurrence .—Pleistocene: Santa Barbara, California (rare). 
Cotypes. —Cat. No. 68465, U.S.N.M. 
Family AETEIDAE Smitt, 1867. 
Genus AETEA Lamouroux, 1812. 
(See Bulletin 106, U. S. National Museum, p. 179, for discussion.) 
AETEA ANGUINA? Linnaeus, 1758. 
Plate 24, fig. 15. 
To this recent species we have referred doubtfully the creeping network of 
a bryozoan from the Pliocene of South Carolina. Without a more complete zoa- 
rium it is impossible to make a more definite identification, but we figure the speci¬ 
men in order to call attention to fossil bryozoa of this type of structure. The 
geological distribution and other features of this species have been given in our 
Monograph on North American Early Tertiary Bryozoa. 
Occurrence. —Pliocene (Waccamaw marl): Waccamaw River, Horry County, 
South Carolina. 
Plesiotype. —Cat. No. 68466, U.S.N.M. 
Family CHAPERIIDAE Jullien, 1888. 
1888. Chaperiidae Jullien, Mission scientifique du Cap Horn, VI, Zoologie, Bryozoaires, p. 61. 
The orifice is semilunar, or subcircular, very large, entirely closed by the 
operculum, provided interiorly with one or more calcareous plates serving for 
the insertion of the retractor muscular fibers of the operculum; the frontal is 
deprived of pores. The ancestrula, of the same form as the zooecia, is oval and 
bears some articulated spines on the border. (Translated after Jullien.) 
Genus CHAPERIA Jullien, 1881 (first group). 
1881. Chaperia Jullien, Remarques sur quelques Especes de Bryozoaires Cheilostomiens, Bulletin 
Soci6t6 zoologique de France, vol. 6, p. 61. 
Two internal calcareous plates, with extremities fixed and serving for the 
insertion of the retractor muscular fibers of the operculum. (Translated, after 
Jullien.) 
Type.—Chaperia ( Flustra ) acanthina Quoy and Gaymard, 1824. Range: 
Miocene—Recent. 
The species of this genus corresponding exactly to Jullien’s definition are: 
Chaperia ( Flustra ) acanthina Quoy and Gaymard, 1824; C. ( Amphiblestrum) 
spinosa MacGillivray, 1881; and C. spinosissima Calvet, 1904. 
The ovicell of these forms has never been figured. Jullien alone affirmed 
(but he has given no figure) that the operculum does not close the ovicell. Waters 
and Calvet classify in the same genus a certain number of other forms with concave 
