NORTH AMERICAN EARLY TERTIARY BRYOZOA. 
781 
IDMONEA FILIFORMIS, new species. 
Plate 138, figs. 24-27. 
Description. — The zoarium is linear, very long, very thin, filiform. The 
fascicles are little salient, arranged alternately on each side of the median line 
and extending very little beyond the zoarial margins; they are formed by two 
zooecia only. The tubes are visible and convex. The dorsal lamella is round 
and smooth. 
Diameter of the tubes 0.15 mm. 
Distance between the fascicles 0.90-1.10 mm. 
Measurements.— width of the fascicles 0.15 mm. 
Width of the zoarium 0.50 mm. 
Affinities. — This species presents the aspect of Idmonea unipora D’Orbigny, 
1852, figured by Beissel, 1865, with two zooecia to the fascicle; but the interfas- 
cicular separation is much greater. 
O ccurrence. — Middle Jacksonian (Castle Hayne limestone) : Wilmington, 
North Carolina (rare). 
Cotypes.— Cat. No. 65418, U.S.N.M. 
IDMONEA PETRI D’Archiac, 184fi. 
Plate 139, figs. 1-13. 
1846. Idmonea petri D'Archiac, Description des fossiles recueillis par M. Tliorent dans 
les couches nummulitiques des environs de Bayonne, Memoires de la Societe 
geologique de France, ser. 2, vol. 2, p. 195, pi. 5, fig. 11. 
1908. Idmonea non reticula Betjtler, Beitrag zur Kenntnis der Bryozoenfauna der iilteren 
Tertiarschichten des siidliehen Bayern, Cyclostomata, Paleontographica, vol. 59, 
p. 226, pi. 23, figs. 17, 18. 
1911. Idmonea petri Canu, Bryozoaires des Sud-Ouest de la France, Bulletin de la Societe 
geologique de France, ser. 4, vol. 11, p. 452, pi. 8, figs. 1-2 et 10-11. 
Description. — The zoarium is large, linear, or somewhat claviform, compressed, 
with triangular transverse section. The fascicles are very salient, close together, 
not extending beyond the zoarial margins, opposite on each side of the median axis: 
they are formed of four to six equal zooecia. The tubes are visible, flat, often 
separated by a salient thread. The basal lamella is somewhat concave, excavated, 
and bordered by a margin of little thickness; it is smooth, slightly striated trans- 
versely and longitudinally. 
Measurements . — 
Diameter of the tubes 
Distance between the fascicles 
Width of the fascicles 
Width of the zoarium 
0.14 mm. 
0.30-0.40 mm. 
0.12 mm. 
1.2 mm. 
Affinities. — The determination has been made specimen by specimen with the 
French material, but it may be possible that this species has been described under 
a nother name by the paleontologists. Idm onea distich a Reuss, figured by Manzoni 
in 1877, is exteriorly very close, but the fascicles are clearly alternated, which is 
