NORTH AMERICAN EARLY TERTIARY BRYOZOA. 
621 
occupy the median part of the young fronds, but they totally overspread the 
fronds at the base of the zoarium; they are globular, very salient, and bear a 
frontal avicularium. The interzooecial avicularia are as large as the zooecia; 
they have a pivot; they are elliptical and their beak is round and little salient; 
they are chiefly disposed on the edge of the fronds. 
Measurements . — Peristomice mm ‘ 
[lpe=0.15 nun. 
Zooecia / 
L2=u.bunnn. 
I lz= 0.35-0.40 mm. 
V aviations . — There are three sorts of branches. The younger ones are formed 
entirely of oriented zooecia (fig. 14) ; the median crest exists, however, and the 
zooecia are there distinct. The older ones have some cumulate zooecia on the 
median crest (figs. 15, 16, 19). Finally, the fragments of the base are uniquely 
covered with cumulate zooecia (fig. 17), among which are found some interzooecial 
avicularia. The presence of the interzooecial avicularia on the edge of the zoarium 
(fig. 18) is inexplicable. The phenomenon is rather frequent in many Cretaceous 
Cheilostomes with olocystal frontal. 
The tangential section (fig. 20) is interesting because it shows the structure 
at different depths; the olocystal elements (fig. 21) are scattered. 
Affinities . — This species differs from Kleidionella lobata in the almost con- 
stant presence of the cumulate zooecia and in its narrower and more elongated 
fronds. 
It differs from Kleidionella 'parasitica in its smaller zooecial dimensions and 
in the very peculiar nature of the fronds. 
Occurrence . — Middle Jacksonian: Near Lenuds Ferry, South Carolina (very 
common). 
Cotypes. — Cat. No. 64224, T7.S.N.M. 
KLEIDIONELLA VERRUCOSA, new species. 
Plate 101, figs. 1-11 ; plate 102, figs. 1^. 
Description . — The zoarium is free, formed of two layers, back to back, of 
cumulate zooecia, bilamellar at the summit, multilamellar at the base; the fronds 
are thick, compressed, elongated, bifurcated. The young zooecia are oriented, dis- 
tinct, elongated; the frontal is smooth, very convex, bears an elliptical avicu- 
larium, salient, with median pivot. The apertura is oval and deep; the peristomice 
is elliptical. The ovicell is hyperstomial, salient, convex, smooth ; it opens widely 
into the peristomie. The cumulate zooecia are salient, ovoid, smooth, often deprived 
of frontal avicularium. The interzooecial avicularia are salient, somewhat larger 
than the zooecia ; they have a pivot and their beak is very round. 
Measurements . — Apertura 
Zooecia 
r/nz=0.12 mm. 
(Za=0.06 mm. 
j Zs=0.5Q-0.60 mm. 
|/,s=0.30 nun. 
V aviations . — The cumulate zooecia are often grouped together as wart-Wce 
projections among the oriented zooecia (pi. 101, fig. 6). The latter are visible 
