NORTH AMERICAN EARLY TERTIARY BRYOZOA. 
81 
opesium is slightly pyriform, the narrow end raised. The normal mode of branch- 
ing is bilateral. 
M easurements . — O p esia 
\ho=0.15 mm. 
„ . f As =0.60-0.70 mm. 
Zooeciaj fe=(X25 _ a30 mm _ 
}/6i=0.05-0.075 mm. 
Certain zooecia bear on the giunnocyst near the opesium a little pore that is 
perhaps the place of a spine. The olocyst appears to be formed of two calcareous 
superposed layers. 
The micrometric dimensions of this species are identical with those of Pyripora 
catenulana Jameson, 1811, relying upon the figures given by Hincks, but the 
small tuberosities of the mural rim in P. tuberculum alone 
distinguish the two species. We have been unable to make 
direct comparison with this living species, and therefore can 
not pronounce on the identity of the two. 
Occurrence. — Middle Jacksonian (Castle Hayne lime- 
stone) : Wilmington, North Carolina (rare). 
PJesiotype. — Cat. No. 63866, U.S.N.M. 
Genus HERPETOPORA Lang, 1914. 
1914. Herpetopora Lang, On Herpetopora, a new genus of Creta- 
ceous Gheilostome Polyzoa, Geological Magazine, dec. 6, 
vol. 1, p. 7. 
Incrusting, uniserial. The mode of branching is 
bilateral. Heteromorphic individuals may occur. The nor- 
mal zooecia consist of a distal k ‘ capitular ” and a proximal 
“ caudal ” portion. Sealed and reversed zooecia very com- 
mon. (After Lang.) 
Genotype. — Herpetopora anglica Lang, 191-1. 
Range. — Cretaceous- Vicksburgian. 
This genus has been confused in part with Pyripora 
D’Orbigny, and even now we do not venture to affirm that 
the Cretaceous species figured by Lang are not the same 
group as Pyripora catenularia. It tvill be necessary to know 
the significance of the heteromorphic zooecia noted by the 
author before the full value of the genus can be determined. 
HoAvever, in case of identity with Pyripora in these respects, Lang’s genus might 
still be maintained for the species devoid of the caudal portion. 
Fig. 22. — Genus Herpeto- 
pora Lang, 1914. 
Several zooecia of Herpe- 
topora anglica Lang, 1914, 
X 27, two of which are nor- 
mal and the third sealed. 
(After Lang, 1914.) Cre- 
taceous (Senonian) : Chat- 
ham, England. 
HERPETOPORA DANICA Lang, 1914. 
Plate 80, fig. 1. 
1914. Herpetopora ddnica Lang, On Herpetopora, a new genus of Cretaceous Cheilostome 
Polyzoa, Geological Magazine, dec. 6, vol. 1, p. 7, pi. 11, figs. 6, 7. 
Species of such elementary structure can hardly be distinguished from each 
other by any other means than their micrometric dimensions. Both the Cretaceous 
species Herpetopora clanica and our specimens from the Vicksburgian have an 
55899— 19— Bull. 106 6 
