MARYLAND GEOLOGICAL SURVEY 741 



Reptoflustrella ? heteropora Ulrich, 1901, Maryland Geol. Survey, Eocene, p. 



213, pi. Ix, figs. 8, 9. 

 Amphiblestrum heteropora Weller, 1907, Geol. Survey of New Jersey, Pal., 



vol. iv, 1907, p. 333, pi. xxiii, figs. 14-16. 



Description. Zoarium encrusting in irregular patches, usually grow- 

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

 arranged with but little regularity, but sometimes exhibiting a tendency 

 to grow in radiating lines, longer than wide, pointed in front, broadly 

 subtruncate behind; aperture about 0.15 mm. in width, subtriangular in 

 outline with convex sides, often approaching an oval form in very long 

 zocecia ; bordered anteriorly and laterally by a slightly elevated, rounded 

 ridge which becomes obsolete posteriorly. Just in front of the anterior 

 angle of the zocecial 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 con- 

 tinued over the entire surface, totally obliterating the aperture. 



Not uncommon in the Vincentown limesand at Vincentown, Mullica 

 Hill and Timber Creek, New Jersey, and at Noxontown Millpond, Dela- 

 ware. Bare in the Eocene (Aquia) at Upper Marlboro, Maryland. 



Occurrence. EANCOCAS FORMATION. Noxontown Millpond, Delaware. 



Collection. Maryland Geological Survey. 



Genus ESCHAR1NELLA d'Orbigny 

 ESCHARINELLA ?? ALTiMURALis Ulrich and Bassler 



Plate XLVI, Fig. 7 



Escharinella altimuralis Ulrich and Bassler, 1907, Geol. Survey of New Jer- 

 sey, Pal., vol. iv, p. 339, pi. xxiv, figs. 9, 10. 



Description. This very characteristic species may be readily distin- 

 guished by its suborbicular zocecia averaging 0.5 mm. in length with their 

 extremely thin Avails and with a very large subelliptical avicularium at 

 each zocecial angle. The generic placement in Escharinella is entirely 

 provisional until this group of species can be thoroughly studied. 



This is an abundant species in the Vincentown limesand at Vincen- 

 town, New Jersey. 



Occurrence. RANCOCAS FORMATION. Noxontown Millpond, Delaware. 



Collection. Maryland Geological Survey. 



