562 BULLETIN 106, UNITED STATES NATIONAL MUSEUM. 



Genotypes. Adeonella polymorpha Busk, 1884, and AdeoneUa (Eschara) 

 polystomella Reuss, 1847. 



Range. Jacksonian Recent. 



ADEONELLA FOLLICULATA Cann and Bassler, 1917. 



Plate 72, figs. 1-8. 



1917. AdeoneUa foUiculata CANTI and BASSLER, Synopsis of American Early Tertiary Cbeilo- 

 storne Bryozoa, Bulletin 96. United States National Museum, p. 66, pi. 6, fig. 3. 



Description. The zoarium bilamellar with two lamellae, back to back, and sep- 

 arable. The fronds are lobed, very thin, and fragile. The zooecia are very long, 

 distinct, separated by a furrow, little convex, bordered with numerous parietal 

 areolae (10-12 pairs). The peristomie is short, somewhat projecting exteriorly 

 and is perforated by a spiramen ; the peristomice is semilunar with a convex lower 

 lit); the aperture (interior) presents a proximal concave border. The gonoecia 

 are (0.30 mm.) larger than the other zooecia; their external aperture is greater 

 (?=0.10 mm.) and the spiramen is more removed from the aperture. There is a 

 very small, simple avicularium on the peristome. 



. JZ.3=0.65-0.75 mm. . . fZs=0.50mm. 



zooecia( ??=a20 _ Axial 



Q onoec - a j/^==0.50mm. Peristomice of fAp=0.04mm. 

 ' U2=0.30mm. zooecia I lp= 0.07 mm. 



Peristomice of |Aj$>=0.04 mm. 

 gonoecia I Zp=0.10 mm. 



Variations. The zooecial walls are so thin and fragile that it is difficult to 

 obtain a good interior presenting all the characters of the species, and it is neces- 

 sary to study this feature by successive rubbing away of the substance. 



The axial zooecia are shorter than the lateral ones (figs. 3, 6), nevertheless there 

 are fronds composed uniquely of long zooecia alone (fig. 4). 



Often one of the parietal areolae is transformed into a small, simple avicu- 

 larium, slightly pointed (fig. 2) and of inconstant position. Just as the zooecial 

 areolae may be transformed into avicularia, the parietal pores resulting from a 

 growth of the ectocyst are susceptible to continuation of evolution, according to 

 the needs of the zoarium. 



The small peristomial avicularium is round; its place is very variable, but 

 always on the distal border. 



The gonoecia are somewhat larger (0.30 mm.) and their external aperture also 

 larger (0.10 mm.) ; the spiramen is placed farther from the external aperture and 

 perhaps it opened exactly at the level of the operculum, instead of being above it 

 (fig. 6). 



Figure 5 represents a very common alteration by fossilization. 



The fronds have the thinness of a leaf and are very fragile. 



Occurrence. Middle Jacksonian ( Castle Hayne limestone) : Wilmington. North 

 Carolina (common). 



Cotypes.Cat. No. 62608, U.S.N.M. 



