334 CRETACEOUS PALEONTOLOGY. 



1864. ReptoHustrella ( ?) heteropora Meek, Check List. Inv. 



Foss. N. A., Cret. and Jur. p. 4. 

 1868. ReptoHustrella ? heteropora Con., Cooks Geol. N. J., p. 



723- 

 1901. ReptoHnstrella heteropora Ulrich, Md. Geol. Surv., 



Eocene, p. 213, pi. 60, figs. 8-9. 

 1905. ReptoHustrella heteropora Johns., Proc. Acad. Nat. Sci. 



Phil., 1905, p. 5. 



Description. Zoarium encrusting in irregular patches, usually 

 growing upon other species of bryozoa. Zooecia in a single layer, 

 usually arranged with but little regularity, but sometimes ex- 

 hibiting a tendency to grow in radiating lines,- longer than wide, 

 pointed in front, broadly subtruncate behind; aperture about .15 

 mm. in width, subtriangular in outline with convex sides, often 

 approaching an oval form in very long zocecia; bordered an- 

 teriorly and laterally by a slightly elevated, rounded ridge which 

 becomes obsolete posteriorly. Just in front of the anterior angle 

 of the zocecal aperture is a small subcircular pore, probably the 

 point of attachment of an avicularium. Posterior portion of the 

 zocecia covered with a regularly convex, smooth wall, which in 

 old zoaria is continued over the entire surface, totally obliterating 

 the aperture. 



Remarks. This species has been identified by Ulrich from the 

 Eocene beds of Maryland, but these Eocene examples are coarser 

 in appearance and- the front wall of the apertural margin is dis- 

 tinctly granular. It is altogether possible that the Eocene ex- 

 amples should be considered as a distinct species. 



Formation and locality. Vincentown limesand, Vincentown 

 (154), Timber Creek and near Mullica Hill (Gabb and Horn). 



Geographic distribution. New Jersey, also Eocene of Mary- 

 land. 



Genus MEMBRANIPORA Blainville. 



Membranipora plebia Gabb & Horn. 



Plate XXIIL, Fig. 17. 



1862. Membranipora plebia G. & H., Jour. Acad. Nat. Sci. Phil., 

 2d ser., vol. 5, p. 158, pi. 20, fig. 43. 



