674 



BULLETIN 106, UNITED STATES NATIONAL MUSEUM. 



Measurements. 



DIASTOPORA STRIATISEMOTA, new species. 



Plate 121, fig. 9. 



Description. The zoarium is formed of wide, expanded fronds. The tubes are 

 indistinct at their base, cylindrical at their extremity, arranged in widespread 

 quincunx, garnished with small thin and scattered striations. The peristome is 

 thin, orbicular, oblique, or elliptical when it is horizontal ; the peristomie is salient, 

 oblique, erect. The basal lamella is smooth. 



Diameter of the peristome 0.10 mm. 



Distance between the peristomes 0.40-0.50 mm. 



Separation of the peristomes 0.40 mm. 



Length of the peristomie 0.12 mm. 



Affinities. This species differs from Diaperoecia ruyosa, new species, by the 



transverse, little salient wrinkles and a lesser 

 zooecial length. 



Occurrence. Upper Jacksonian (Ocala 

 limestone) : Chipola Eiver, east of Marianna, 

 Jackson County, Florida (very rare). 



Middle Jacksonian: Seventeen miles 

 northeast of Hawkinsville, Georgia (rare). 



Holotype.Cnt. No. 65300, U-S.N.M. 



DIASTOPORA MAGNIPORA. new species. 



Plate 153, figs. 3, 4. 



Description. The zoarium is formed of 

 a unilamellar and flabellate frond. The 

 tubes are enormous, wide, oval, distinct at 

 their base, somewhat upward bent. The 

 peristome is very thick, orbicular, or ellipti- 

 cal, very salient; the peristomie is short, 

 raised to 45. 



Diameter of the peristomes 0.20-0.24 mm. 



Diameter of the apertura 0.10-0.12 mm. 



Distance between the peristomes 0.70-0.80 mm. 



Separation of the peristomes 0.64 mm. 



Length of the peristomie 0.32 mm. 



Occurrence. Vicksburgian (Marianna limestone) : Salt Mountain, 5 miles 

 south of Jackson, Alabama (very rare). 

 Holotype.Qrt. No. 65380. U.S.N.M. 



Forma SPIROPORA Lamouroux, 1821. 



1821. Spiropora LAMOURODX, Exposition Melhodique de* Polypiers, p. 47. 



The apertures of the zooecia open in regular annular or spiral lines. The 

 zooecia are regularly cylindrical. 



FIG. 218. Forma Spiropora Lamouroux, 



1821. 



A. Zoariuui, of Spiropora Mragona 

 Lamouroux, 1821. B. Longitudinal sec- 

 tion, through half of zoarium of 

 Spiropora riclimondensis Vine, 1S84. 

 (After Gregory, 1896.) 



Measurements. 



