XORTH AMERICAN LATER TERTIARY AND QUATERNARY BRYOZOA. 
63 
salient, finely granular. The cryptocyst is finely porous; the opesium is irregular or 
semilunar, a little elongate; the polypidian tube forms a rectangular surface, salient 
and excentric between the two dissimilar opesiular indentations. The large zooecia 
(B) are provided with a wide distal floor, and the polypidian tube is almost median. 
,, . r\ • t n / \ • (/to = 0.34-0.36 mm. 
Measurements. —Opesium of small (a) zooecia.. 7 _ 
r fo = 0.16-0.30 mm. 
Small (a) zooecia_ 
Opesium of large (B) 
Large (B )zooecia_ 
(is = 0.50-0.76 mm. 
j fe = 0.50 mm. 
/io = 0.24-0.30 mm. 
lo = 0.36-0.40 mm. 
Lz= 1.00-1.10 mm. 
Iz = 0.44—0.56 mm. 
Affinities. —The dimensions are quite variable, but they are always smaller than 
those of Steganoporella magnilabris Busk, 1854, which this species resembles in all 
its other characters. 
A. Steganoporella B. Siphonoporella 
Fig. 7.—Genera of the family Steganoporellidae Levinsen, 1909. 
A. Steganoporella Smitt, 1873. S. magnilabris Busk, 1852. Recent. (After Harmer, 1900.) 
B. Siphonoporella Hincks, 1880. S. delicatissima Busk, 1840, X40. Recent. (After Levinsen, 
1909.) 
Occurrence. —Lower Miocene (Bowden horizon): Cercado de Mao, Santo Do¬ 
mingo (rare) and Bowden, Jamaica (common). 
Cotypes. —Cat. Nos. 68485, 68486, U.S.N.M. 
STEGANOPORELLA MAGNILABRIS Busk, 1854. 
Plate 14, figs. 12, 13. 
1854. Membranipora magnilabris Busk, Catalogue Marine Polyzoa, British Museum, pt. 2, 
Cheilostomata, p. 62, pi. 65, fig. 4. 
1872. Steganoporella elegans Smitt, Floridan Bryozoa, collected by Count Pourtales, Pt. I, Kongl. 
Svenska Yetenskaps-Akademiens Handlingar, vol. 10, No. 11, p. 15, pi. 4, figs. 96-101. 
1890. Steganoporella magnilabris Harmer, A revision of the Genus Steganoporella, Quarterly 
Journal Microscopical Science, vol. 43, p. 279, pi. 12, fig. 10; pi. 31, figs. 44-46 (cites bibli 
ography). 
1909. Steganoporella magnilabris Levinsen, Morphological and Systematic Studies on the Cheilo- 
stomatous Bryozoa, pp. 167, 168. 
