210 SYSTEMATIC PALEONTOLOGY 



also appear to be smaller and the apertures of both zooecia and meso- 

 pores smaller, more angular and less regularly disposed than in C. ra- 

 mosa. 



Occurrence. — Aquia Fokmation'. Upper Marlboro (in fragments). 



Collection. — Maryland Geological Survey. 



Genus CERIOPORA Goldfuss. 



Ceeiopoea micropoea Goldfuss. 

 Plate LIX, Figs. 13, 14. 



Ceriopora micropora Goldfuss, 1823, Petr. i, p. S3, pi. x, fig. id (not 4«-c). 

 Ceriopora micropora Hagenow, 1851, Die Bryozoen der Maastriehter Kreide bildung, 

 p. .52, pi. Y, fig. 4. 



Description. — Among the Survey material received for description is a 

 single zoarium agreeing too closely with C. micropora, as redefined by 

 Hagenow and represented by several examples in the author's private 

 collection received from Dr. Ed. Pergens, to admit of distinguishing it 

 at present. The specimen is depressed globular in shape, nearly 5 mm. 

 in diameter, hollow beneath, and composed of at least three layers of 

 zooecia. The zooeeial apertures are not very clearly shown by the speci- 

 men but appear to be a trifle smaller, more unequal and thinner walled 

 than in the Maastricht colonies. 



Occurrence. Nanjemoy Foemation. 2-^ miles above Popes Creek. 



Collection. — Maryland Geological Survey. 



Genus HETEROPORA Blainville. 



Heteeopoea (?) tecta n. sp. 



Plate LIX, Figs. 15, 16. 



Description. — Zoarium consisting of small, subramose masses or stems, 

 2 or 3 mm. in thickness, the upper ends of which are rounded and cov- 

 ered uniformly with angular thin-walled tube mouths, about seven in 

 1 mm. A large proportion of the sides of the specimen figured is cov- 

 ered with a thin and minutely punctate pellicle, the tube apertures 

 covered thereby being quite obscured. Most of the apertures showing 

 through or piercing the pellicle, are of rounded form, with an inside 

 diameter of about 0.13 mm., and enclosed by a ring-like peristome. 



