774 
BULLETIN 106, UNITED STATES NATIONAL MUSEUM. 
1887. Idmonea milneana Waters, Bryozoa from New South Wales, Annals Magazine Nat- 
ural History, ser. 5, vol. 20, p. 256. 
1888. Idmonea milneana Waters, On some ovicells of Cyclostomatous Bryozoa, Journal 
Linnean Society, London, Zoology, vol. 20, p. 279, pi. 14, fig. S. 
1SS9. Idmonea milneana Jelly, A Synonymic Catalogue of the Recent Marine Bryozoa, 
p. 118. 
1S90. Idmonea milneana Ortmann, Die Japanisclie Bryozoen-Fauna, Archiv. fur Nat- 
urgeschichte, vol. 1, Heft 1, p. 59, pi. 4, fig. 21. 
1905. Idmonea milneana Waters, Bryozoa from near Cape Horn, Journal Linnean Society. 
London, vol. 29. p. 249 (habitat). 
1908. Idmonea milneana Canu, Bryozoaries fossiles du Sud-Ouest de la France, Bulletin 
Soeiete geologique France, ser. 4, vol. S, p. 386. pi. 7, fig. 16. 
1909. Idmonea milneana Canu, Bryozoaires tertiares des environs de Paris, Annals de 
Paleontologie, p. 125 (53), pi. 14, figs. 11, 12, 13. (Paleontologic bibliography). 
1910. Idmonea milneana Canu, Bryozoaires fossiles du Sud-Ouest de la France, Bulletin 
Soeiete geologique de France, ser. 9, vol. 10. pi. 840. 
1911. Idmonea milneana Canu, Bryozoaires fossiles de Sud-Ouest de la France, Bulletin 
de la Soeiete gfiologique, ser. 4. vol. 11, p. 451, text, fig. 6. (ind.). 
1914. Idmonea milneana Waters, The marine fauna of East Africa and Zanzibar, Proceed- 
ings of the Zoological Society of London, p. 844. 
Description. — The zoarium is bifurcated, compressed with elliptical transverse 
section broader than high. The fascicles are scattered, little salient, arranged alter- 
nately on each side of the median axis; they are formed of three zooecia, the first 
of which is isolated. The tubes are visible, convex, with thin peristome. The 
basal lamella is convex, more or less striated transversallv ; the tubes are visible 
longitudinally. 
,, , fDiameter of the tubes 0.16-0.20 mm. 
casmemen s. 1 Distance between the fascicles 0.40-0.60 mm. 
Tarnations.- — This species is rather constant in its characters and its determi- 
nation is easy. We have not had the chance to discover its ovicell, but this has 
been figured by Waters and Smitt; it must, probably occur very rarely. 
The width of the zoarium varies between 0.80 mm. (fig. 4) and 1.33 mm. 
(fig. 3). The striations of the basal lamella are generally little deep; rarely they 
are accentuated (fig. 5). 
The dorsal tangential section reveals the spindles characteristic of all the 
cyclostomatous bryozoa in which the basal lamella is not reinforced (fig. 12). 
The microscopic structure of the tubes is identical on the basal lamella (fig. 9) 
and on the frontal face (fig. 8). The basal lamella has therefore no particular 
reality; it results simply from the agglomeration of the tubes which are closely 
united together. 
Occurrence. — Middle Jacksonian (Castle Hayne limestone) : Wilmington, 
North Carolina (very common). 
Vicksburgian (Red Bluff clay) : One-fourth mile west of Woodwards, Wayne 
County, Mississippi (very rare). 
Geological distribution . — Ypresian of England (Gregory) ; Lutetian of the Paris 
Basin (Gregory, Canu), of the Bordeaux Basin (Canu), of the French Pyrenees 
