350 
BULLETIN 100, UNITED STATES NATIONAL MUSEUM. 
thread; the frontal is convex, smooth, with the radial nerves visible by transpar- 
ency. The aperture is small and bears on its proximal border a rather wide trian- 
gular rimule. Above the aperture there are two small, simple avicularia. 
M easurements . — Apert u re 
\ha= 0.12 mm. 
lZ«=0.10 mm. 
Zooecia 
Lz= 0.65-0.75 mm. 
fe=0.45-0.50 mm. 
Affinities . — This species differs from Buffonella rhomb oiddlis in its longer 
zooecia, in the salient separating thread, and the presence of two small supraoral 
avicularia. 
The same characters also differentiate it from Buffonella incisa Reuss, 1874. 
Occurrence . — Middle Jacksonian (Castle Havne limestone) : Wilmington, North 
Carolina (rare). 
Holotype.— Cat. No. 64053, U.S.N.M. 
BUFFONELLA RHOMBOIDALIS, new species. 
Plate 46, fig. 2. 
Description . — The zoarium incrusts bryozoa. The zooecia are distinct, elon- 
gated rhomboiclal , separated by a furrow; the frontal is convex and absolutely 
smooth. The aperture is small, without peristome; the rimule is large and rectan- 
gular. 
M easurements . — Aperture 
} ha= 0.12 mm. 
l7a.=0.10 mm. 
Zooecia 
j ZA=0.55-0.65 mm. 
lfe= 0.40-0.50 mm.. 
Affinities . — This species resembles Buffonella incisa Reuss, 1874, very much, 
in its extreme simplicity of structure. It differs from it only in its larger 
micrometric measurements (Ls— 0.55-0. 65 mm. instead of 0.36-0.40 mm.). 
Occurrence . — Middle Jacksonian (Castle Havne limestone) : Wilmington, 
North Carolina (very rare). 
Holotype. — Cat. No. 64054, U.S.N.M. 
BUFFONELLA MICROSTOMA, new species. 
Plate 46, fig. 3. 
Description . — The zoarium incrusts shells. The zooecia are very small , elon- 
gated, distinct; the frontal is smooth and convex. The aperture is very small; the 
rimule is wide and triangular. The ovicell is globular, salient, and smooth; it 
opens above the aperture by a small slit; it may be closed by the operculum. 
Measurements . — Aperture 
| Aa.=0.06 mm. 
1 ?«.= 0.06 mm. 
Zooecia 
[Zs=0.35 mm. 
|fe=0.20 mm. 
Affinities .- — This species differs from Buffonella incisa Reuss, 1874, in its 
slightly smaller micrometric dimensions and in its rimule. which is triangular and 
not rectangular. Moreover, the European fossil sometimes bears a small, lateral 
avicularium, which we have not observed on the American specimens. 
