. Bulletin - United States National Museum. Science. NORTH AMERICAN LATER TERTIARY AND QUATERNARY BRYOZOA. 141 Measurements.—Apertura., „',' ^ lia = mm. Zooecia Zz = mm. Uz = mm. Affinities.—This species is very easy to recognize by its intcrareolar radiating costules; however, this character is much less apparent on the zooecial margins where the pleurocystal calcification is incomplete. Occurrence.—Pliocene (Caloosahatchee marl): Shell Creek, De Soto County, Florida (very rare). Holotype.—Cut. No. 68634, Family EURYSTOMELLIDAE Levinsen, 1909. Levinsen's original de
. Bulletin - United States National Museum. Science. NORTH AMERICAN LATER TERTIARY AND QUATERNARY BRYOZOA. 141 Measurements.—Apertura., „',' ^ lia = mm. Zooecia Zz = mm. Uz = mm. Affinities.—This species is very easy to recognize by its intcrareolar radiating costules; however, this character is much less apparent on the zooecial margins where the pleurocystal calcification is incomplete. Occurrence.—Pliocene (Caloosahatchee marl): Shell Creek, De Soto County, Florida (very rare). Holotype.—Cut. No. 68634, Family EURYSTOMELLIDAE Levinsen, 1909. Levinsen's original description is as follows: No spines. The thick-walled and strongly calcified zooecia lack a covering membrane and have either no pores at all or 2-5 extremely large fenestrae. The broad aperture, which has a concave proxi- mal rim, is provided with a more or less strongly chitinized operculum surrounded by a continuoiis marginal thickening. No avicularia. The ooecium is enclosed in a kenozooecium, the frontal wall of which is provided with a very large uncalcified part. Pore-chambers [dietellae] or groups of uniporous rosette-plates [septulae]. The two known species classed in this family are Lepralia foraminigera Hincks, 1883, and Lepralia bilahiata Hincks, 1884. Levinsen believed that the second species is probably the type of a special genus while the first is the type of the genus Eurystomella. tat men. Fig. 26.—Genus Eurystomella Levinsen, 1909. A-C. Eurystomella bilahiata Hincks, 1884. A. Sketch showing the operculum dissected out; r6, outer rib; rb', inner rib; in. op., inner operculum; or, orifice; lat. mem., lateral membrane; fd. mem., folded membrane; ac, accessory lip; ou. op., outer operculum. B. A few adult zooecia, X 30; th. r, thickened rim; op, operculum; urn, umbo; /;, keel. C. A few zooecia at the growing edge of the colony ehoiring the membranous aperture of the immature zooecia ( zoe.) (A-C, after Robertson, 1908.) D-F. Eurystomella foraminige
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