NORTH AMERICAN EARLY TERTIARY BRYOZOA. 



81 



opesium is slightly pyriform. (he narrow end raised. The normal mode of branch- 

 ing is bilateral. 



-,, ^ . \ho=0.15 mm. . ILsO.fiO-O.'iO mm. 



Measurements. Opesia , Zooecia 7 



^0=0.0o-0.075 nun. \ls-0.2o-0.30 mm. 



Certain zooe<-ia hear on the gymnocyst 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 

 ,-<rffnH/ttrt(t. Jameson, 1814, relying upon the figures given by Hincks, but the 

 small tiibemsities 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, Xorth Carolina (rare). 

 PI, xlvtyp, .Cat. Xo. 63866, U.S.N.M. 



Genus HERPETOPORA Lang, 1914. 



T.I14, lli-rii<-tr,iHirit LANG, On Herpetopora, a new genus of Creta- 

 ceous Cheilostome Poly/oa. ideological Magazine, dec. i;, 

 vol. 1. p. 7. 



Incrusting, uniserial. The mode of branching is 

 bilateral. Heteromorphic individuals may occur. The nor- 

 mal zooecia consist of a distal "capitular" and a proximal 

 " caudal " portion. Sealed and reversed zooecia very com- 

 mon. (After Lang.) 



Genotype. Herpetopfir.t mn/ln-n. Lang, 1914. 

 Iiinn/c. Cretaceous- Vicksburgian. 



This genus has been confused in part with Pyripom 

 D'Orbignv, and even now we do not venture to affirm that 

 the Cretaceous species figured by Lang are not the same 

 group as Pi/ripnnt catenularia. It will be necessary to know 

 the significance of the heteromorphic zooecia noted by the ham, England, 

 author before the full value of the genus can be determined. 



However, in case of identity with Pi/riporu in these respects, Lang's genus might 

 still be maintained for the species devoid of the caudal portion. 



HERPETOPORA DANICA Lang. 1914. 



Plate 80. fig. 1. 



T.U4. Jlrriiiiniinrii itiuiicu LANG. (Mi Herpetopora, a new genus of Oetacecius ( 'heilostoine 

 Polyzoa. Geological Magazine, dec. 6, vol. 1, p. 7, pi. 11, tigs. 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 //////</>/ danica and our specimens from the Vicksburgian have an 

 55899 19 Bull. 10G 6 



FIG. 22. Genus Herpelo- 



pora Lang, 1914. 

 Several zooecia of Hcrpr- 

 topora anglica Lang, 1914, 

 X 27, two of which are nor- 

 mal and the third sealed. 

 (After Lang, 1914.) Cre- 

 taceous (Senonian): Chat- 



