Plate 2. 



Fii:s. 1-.'!. clieilojioia hihinfiii I'Iricli. lliOl (p. ri2<i). 



1. 2. Surface of tbe inc-rustin.g tyiie-siieoimeii. X 20. ;iik1 two zooei'ia more eulari-'t'd. (Afior 

 ririch. T.Hn.i 

 ;.!. I'hotograpli of aiioilicr cxaiiiiilo. '■; 2ii. 



Lowest Koceno ( I'.ryo/.oau bed at base of Aquia foniialbni ) : T'lipor Marllmro, 

 Maryland. 



Cat. No. G:!TS:',, f.S.X.M. 

 Fius. 4. .">. Mviiixroijoni siihijhiiiu I'lrieU, I'.Jdl (p. mC>\. 



4. Edge of a specimeu, X 20, sbowiug four layers of zooeeia. 



.'). Surface of tli(> nuiltilaniellar. iiicrustiii^' zo.-irinm. X 20. (Figs. 4. 5, after T'lridi, 

 1001.) 

 Lowest Eocene (Iti'vozoau bed at liase nf Acpiia fnrnialion): Upper Jlarbioro. 

 Maryland. 

 Fig. (!. Ai-diifliioiicUii .liiiiiiJe.r, new species (p. GIT). 



The free b'ilamellar type-specimen, X 20. The large salient avicnlarinin iiml tlie 



flat lyrula are quite visible. 

 Lowest Eocene (Bryozo.-m bed at liase of Atpiia formation): T'pper Marlboro, 

 Maryland. 



Cat. No. 63784. U.S.N.iL 

 FiCiS. 7-22. Co.iciiinpleitra (figitatd Morton. ls.'i4 (p. 27-" i. 



7,8. Surface of tbe Eocene form of this species, X 20, and a zooeciinu more liigbly 

 magnified. (After Ulricb, lOol.) 

 0. Siu-face of a fragment, X 20. 



10. Another fragment. X 20, with vibracnlar zooeeia along the margin. 



Lowest Eocene (Rryozoan bed at base of Aquia formation*: Upper Marll^oro, 

 Maryland. 



Cat, No, 6378.=;, U.S.N.M. 



11. Four fragments of the bifoliate zoavinm, natural size. One preserves the exiianded 



base. 



12. Edge of a zoarinm, X 20, e.xhibiting l)oth vibracnlar and hydrostatic zooeeia. 



13. Another specimen, X 20, with vibracnlar zooeeia only, along the margin. 



14. Transverse section, X 20, 



1.5. Tangential thiu section of a zooecium, X 100. showing olocystal structure 



16. Tangential thin section of a vibracnlar zooecium, X 100. 



17. View of the interior of the zooeeia, X 20, showing one distal and two lateral septulae, 



18. Interior of tlie hydrostatic zooeeia, X 20. The aperture is replaced by a small pore. 

 IfV. Interior of the ordinary zooeeia, X 20. A collar with two small biteral grooves is 



shown in the ai)erture. 



20. Longitudinal section, X 20, showing the lateral septulae. 



21. Portion of a branch, X 20. iu which hydrostatic zooeeia occupy the entire breadth. 



22. A fragment, X 25, with nnnierons ovieelled zooeeia. 

 Cretaceous (Vineeutown i : Vincentown, New .lersey. 



Cat. No, 637S0, U,S,N.M. 

 Figs. 23, 24. Coscinopleitra cHo D'Orbigny, 1852. 



23. A'iew of the surface, X 20, showing a vibracnUun with pi'rforaled lamina (, =cribri 



form area). 



24. Another photograph. X 20, illustrating zooeeia with calcified apertures. 

 Cretaceous of Franca 



3 



