NORTH AMERICAN LATER TERTIARY AND QUATERNARY BRYOZOA. 101 
(Busk), of Italy (Manzoni); Sicilian of Italy (Neviani, Waters); Quaternary of 
Italy (Neviani); Pliocene of New Zealand (Waters). 
Habitat.—Asdic Ocean: Kara Sea, Spitzberg, Greenland, Jean Mayen (160-180 
meters), Alaska (circumpolar species). Eastern Atlantic: North Sea, English 
Channel, England, Brittany, Gulf of Gascony (166 meters), Spain, Madeira (48 
meters), Azores (130 meters). Western Atlantic: Woods Hole region (5-32 meters), 
Florida (14-97 meters). Eastern Pacific: Queen Charlotte Islands, California (213 
meters). Western Pacific: Japan. Southern Pacific: Australia, New Zealand. 
Mediterranean: Nice, Naples, Corse (22-110 meters), Ajaccio (280 meters), Boni¬ 
facio (55-77 neters), Algeria (121 meters), and north of Morocco (370 meters). 
Plesiotypes. —Cat. Nos. 68544-68546, U.S.N.M. 
Genus STYLOPOMA Levinsen, 1909. 
1909. Stylopoma Levinsen, Morphological and Systematic Studies on the Cheilostomatous Bryozoa, 
pi. 18 (name only). 
1920. Stylopoma Canu and Bassler, Monograph North American Early Tertiary Bryozoa, Bull. 
106, U. S. National Museum, p. 359. 
The ovicell is hyperstomial; it covers the apertura and the avicularia entirely. 
The frontal is a tremocyst. The apertura is provided with a small linear rimule. 
Fig. 15.—Genus Stylopoma Levinsen, 1909. 
A.-H. Stylopoma spongites Pallas, 1766. A. Zooecium, X 40, with an ovicell, the frontal half of 
which is cut away. B. drawing, X 6, showing an ovicell from the proximal end and distal walls with 
septulae. C, D. Opercula, X 100. (A-D, after Levinsen, 1909.) E. Zooecia, X 25, showing ovicell 
and vicarious avicularium. F. A zooecium, X 85, showing the oral denticles from the front. G. 
Operculum, X 85. (E-G, after Waters, 1918.) 
Genotype.—Stylopoma ( Eschara ) spongites Pallas, 1766. Range: Miocene- 
Recent. 
Levinsen proposed this genus for Eschara spongites and Schizoporella longirostris 
Hincks, 1886, but having recognized that the size of the rimule upon which he based 
it is not a generic character, he suppressed the name. We reestablish the genus, 
basing it upon the function of the passage of the eggs, which operates in a very 
different manner from that in Schizopodrella, where the species would otherwise 
have been placed. The great development of the ovicell above the aperture assures 
this function. Schizoporella longirostris Hincks, 1886, has the same type of orifice, 
but not being provided with this ovicell it must be classified in Schizopodrella. 
