NORTH AMERICAN EARLY TERTIARY BRYOZOA. 
533 
convex and formed of a tremocyst with very numerous pores placed on a very 
finely perforated olocyst, from which it is separable. The apertura is formed of 
a very large orbicular anter and of a narrower poster with proximal lip straight 
and denticulated; the testibular arch is clearly visible. The endozooecial ovicell 
is immense and takes the place of a zooecium; it is convex and perforated with 
tremopores; the apertura of the ovarian zooecia is much larger. Two auriculate 
vibracula are placed symmetrically on the distal part of the zooecia. 
Measurements.-— Apertura ha= 0.25 mm. „ . (££’=0.90-1.10 mm. 
of ordinary zooecia la— 0.28 mm. ooecia j^ s= o.80_1.00 mm. 
Apertura of] Ac!=0.25 mm. 
ovarian zooecia da— 0.35 mm. 
V aviations. — Numerous zooecia are closed at the level of the vestibular arch 
by a sort of finely perforated operculum. They probably do not contain a polypide, 
which perhaps died of disease. 1 The phenomenon is frequent in the family. The 
two superposed frontals are clearly visible in figure 12; the tremopores are tubular 
(fig. 11). 
The vibracula are quite constant. We think that the zoarium was not fixed 
at the bottom of the seas, that it was attached to the algae, and that the vibracula 
assure stabilization. There were five septulae. 
Occurrence. — Middle Jacksonian: Wilmington, North Carolina (common); 
31 miles north of Grovania, Georgia (very rare). 
Upper Jacksonian (Ocala limestone) : Old Factory, 11 miles above Bainbridge, 
Georgia (rare). 
i lotypes . — Cat. No. 62604, U.S.N.M. 
Genus METRARABDOTOS Canu, 1914. 
1914. Metrarabdotos Cant:, Bryozoaires des Terrains du Sud-Ouest de la France, Bulletin 
Society Geologique, France, vol. 14, p. 472. 
The ovicell is endozooecial. The apertura is semilunar, with a rimule and 
lyrula. The frontal is surrounded with lateral areolae and formed of an olocyst 
surmounted by a pleurocyst. 
Genotype. — Metrarabdotos ( E scliar a) moniliferum Milne-Edwards, 1836. 
Range. — Priabonian-Astian. 
METRARABDOTOS MONILIFERUM Milne-Edwards, 183G. 
Plate 98, figs. 1-10. 
1836. Eschar a monilifera Milne- Edwards, llecherclies anatomiques, physiologiques et zoo- 
logiques sur les Eschares, Annales Sciences Naturalles Zoologie, ser. 2, vol. 6, p. 27, 
pi. 9, fig. 1. 
1844. Eschara punctata Philippi, Beitrage zur Kenntniss der Tertiiirver steiner ungen des 
nordwestliclien Deutselilands, pp. 38, 68, pi. 1, fig. 19. 
1 For the paleopathology the reader should consult the following: 1913-1916. Dr. Rene Larger. La 
contre evolution ou d4g<5n6rescence par Ph6r6dite pathologique cause naturelle de l’extinction des groupes 
animaux. Essai de pal^opathologie g6n£rals compare, Bulletin et M£moires de la Soci6t6 d’Anthropologie 
de Paris, 1913. 
