NORTH AMERICAN EARLY TERTIARY BRYOZOA. 
743 
of the ancestrula. The tubes are distinct, cylindrical or horn-shaped, nearly recti- 
linear, arranged in quincunx, very slightly striated; the peristomie is very salient, 
raised at the center, quite oblique on the zoarial margins; the peristome is elliptical, 
horizontal. The ovicell is globular, salient, transverse, elliptical, located on the 
zoarial margin. No zone of growth. 
[Diameter of the peristome 0.10-0.14 mm. 
Measurements. — Distance between the peristomes 0.30-0.40 mm. 
I Separation of the peristomes 0.20-0.24 mm. 
Variations — The ovicell is almost always placed on the zoarial margin; how- 
ever, when the lobe is large and developed, it may be placed in the middle, and is 
oriented more or less longitudinally. 
The secondary lobes do not originate from the preceding one bv dichotomiza- 
tion as in Proboscina ; they are produced by rejuvenescence — that is to say, by the 
development around a single marginal tube of the preceding lobe, serving thus 
as a pseudo-ancestrula. 
The zone of growth is very narrow and scarcely visible. 
This species is very prolific; one of our specimens shows three successive and 
parallel ovicells on the same tube. 
The tubes are very often horn-shaped and consequently narrowed in their 
proximal portion. 
Affinities. — In its micrometric measurements this species is quite close to 
Plagioecia botula , but it differs in its zoarial form of successive lobules and in the 
very different nature of its ovicell. 
Occurrence. — Middle Jacksonian: Wilmington, North Carolina (rare); 'Rich 
Hill, five and one-half miles southeast of Knoxville, Crawford County, Georgia 
(common). 
Cotypes. — Cat. Nos. 65426, 65427, U.S.N.M. 
DIAPEROECIA LOBULATA, var. PARVIPORA, new variety. 
Plate 122, figs. 8, 9. 
This variety presents the essential characters of the species — marginal ovicell 
and successive lobules produced by rejuvenescence. The only difference is in the 
diameter of the peristome, which measures only 0.06-0.08 mm. 
Occurrence. — Middle Jacksonian: Near Lenuds Ferry, South Carolina (very 
rare) ; Eutaw Springs, South Carolina (very rare). 
Hototype. — Cat. No. 65428 U.S.N.M. 
DIAPEROECIA RUGOSA, new species. 
Plate 153, figs. 5-8. 
Description. — The zoarium incrusts shells and especially cheilostomatous 
bryozoa ; it emits short, foliaceous, bilamellar expansions. The tubes are indistinct, 
arranged in regular quincunx, garnished with large transverse, overlapping, widely 
spaced wrinkles , and are terminated by a very short, oblique peristomie. The 
