. Bulletin - United States National Museum. Science. 294 BULLETIN 100, UNITED STATES NATIONAL, MUSEUM Genus RAGIONULA Canu and Bassler, 1927 The ovicell is hyperstomial, opening into the peristomie, not closed by the operculum. The frontal is (in appearance) a very thick, granular pleurocyst. The apertura is semicircular. The peri- stomice bears a pseudorimule bordered by a small eccentric peri- stomial avicularium. The operculum and the mandible are of the type of Porella. Genotype.—Ragionula {Eschara) rosacea Busk, 1856. Fig. 124.—Genus Ragionula Canu and Bassler, 1927 A-N. Ragionul
. Bulletin - United States National Museum. Science. 294 BULLETIN 100, UNITED STATES NATIONAL, MUSEUM Genus RAGIONULA Canu and Bassler, 1927 The ovicell is hyperstomial, opening into the peristomie, not closed by the operculum. The frontal is (in appearance) a very thick, granular pleurocyst. The apertura is semicircular. The peri- stomice bears a pseudorimule bordered by a small eccentric peri- stomial avicularium. The operculum and the mandible are of the type of Porella. Genotype.—Ragionula {Eschara) rosacea Busk, 1856. Fig. 124.—Genus Ragionula Canu and Bassler, 1927 A-N. Ragionula rosacea Busk, 1856. A-E. Different aspects of zoaria, natural size. F. Adult zooecia, X40. G. Ovicelled zooecia. (After Norman, 1868.) H. A young zooecium showing the avicularium before it is enclosed in the peri- stomice, X40. (F, H. After Hincks, 1880.) I. Aspect of the marginal zooecia and the basal lamella. J. A zooecium seen in profile. K. Portion of a zoarium in which the zooecia are indistinct and ornamented with an avicularium. L. The poriform avicularium, much enlarged. (I-L, after Smitt, 1867.) M. Operculum, X85. N. Mandible of peristomial avicularium, X250. (M, N. After Waters, 1900.) Waters, 1900, has figured the operculum of the genotype; it is the operculum of a Porella. The genus would then belong to the Smittinidae where, however, the oral avicularia are median. We know that external appearances are very deceiving and that the deduction of Waters is quite logical. Canu and Bassler have figured the Smittinidae ornamented with In order to facilitate determination we leave the genus provi- sionally in the Stomachetosellidae. "North American Early Tertiary , pi. G-', flg. 7, pi. 64, fig. 22, pi. 95, flg. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original United Stat
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