742 BULLETIN 106, UNITED STATES NATIONAL MUSEUM. 



or clavate, striated transversally, bent upward at their extremity and terminated 

 by a more or less salient peristome; the peristome is orbicular and thick. The 

 ovicell is large, transverse, globular, traversed by the tubes which conserve their 

 reciprocal positions. 



Diameter of the peristome 0.10-0.12 mm. 



Zooecial diameter. _ _ 0.20 mm. 



Measurements. . , ,, . c n IA 



Distance between the orifices 0.40 mm. 



Separation of the peristomes__ . 0.40 mm. 



Diameter' of the peristome __ 0.10 mm. 



Zooecial diameter 0.16 mm. 



Distance between the orifices. _ _ 0.50-0.60 mm. 



Measurements of 

 Stomatoporoid- 

 portion. 



The micrometric measurements of this species are quite variable; those which 

 we give are quite approximative. 



Affinities. The species is very remarkable in its zoarial aspect which appears 

 more often like a palm leaf at the end of a long stem. In the old zoarial classifica- 

 tion it would be impossible to give this species a generic name, since it affects suc- 

 cessively the forms of Stomatopora, Proboscina, and Bercnicea. This phenomenon 

 has been noted, moreover, rather frequently in the literature, and a most con- 

 vincing example was figured by Hincks as long ago as 1880 in Stomatopora 

 johnstoni. 



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

 North Carolina (very rare). 



Holotype.Cat. No. 65276, U.S.N.M. 



DIAPEROECIA JACKSONIENSIS. new species. 



Plate 121, figs. 12-13. 



Description. The zoarium incrusts shells in claviform branches. The tubes 

 are distinct, cylindrical, arranged in quincunx, finely punctate, with the peristomie 

 salient, oblique, and elevated to 60 ; the peristome is orbicular, oblique. The 

 ovicell is salient, globular, inclosing a dozen tubes; the oeciostome is elliptical, 

 little salient, joined to a tube. 



Diameter of the peristome 0.12 mm. 



Distance between the peristomes 0.60 mm. 



Width of the zoarium 1.7 mm. 



The figured specimen is the only one that has been discovered. 



Occurrence. Lower Jacksonian (Moodys marl) : Jackson, Mississippi (very 

 rare. ) 



Holofype.Cnt. No. 65302, U.S.N.M. 



DIAPEROECIA LOBULATA, new species. 



Plate 122, figs. 1-7. 



Description. The zoarium is free and tubular or incrusts shells; it is formed 

 of successive, flabellate lob-ulex more or less symmetrically arranged on each side 



Measurements. 



