Plate 5. 



[After Dybowski.] 



Callopora nianmiformis Hall. 



Fig. 1 a, b. Three tangential sections (Kuckers). 



Ic. A tangential section showing more angular zooecia (Reval). 



Id, e. Two tangential sections (Wesenberg). 



1/, Ig, Ih. Two tangential and a vertical section of a Prasopora from Cincinnati, 



incorrectly referred here, 

 li. Surface of a zoarium showing covers to apertures (Wesenberg). 

 Ik. Surface showing monticules. 

 IZ. Vertical section showing characteristic tabulation of zooecia and mesopores 



(Kuckers). 

 Zones 1 and 2, various localities. 



Heliolites duhia Fr. Schmidt [not a bryozoan]. 



2 a. Tangential and vertical sections. - 

 Silurian, Hapsal. 



Callopora heterosolen Keyserling. 



3. Outlines of variously shaped zoaria (Reval, Erras, Kuckers, and Baltisch- 



port). 

 3a. Vertical section through the upper part of a zoarium. 

 36. Vertical section through the basal part of a zoarium. 

 3c and d. Tangential sections through the upper and basal parts of the zoarium, 



respectively. 



Zone 1 [B-D], various localities. 



Callopora maculata, new species. 



4. Fragment of a zoarium, natural size. 

 4a. Vertical section. 



46. Tangential section. 



Zone 8 [Silurian], Ohhesare-pank. 



Callopora ligniformis, new species. 



5. Tangential section. 

 5a. Vertical section. 



Zone 2 [D], Wassalem. 



Callopora piriformis Eichwald sp. 



6. Three zoaria, X2/3. 

 6a. Tangential section. 

 66. Vertical section. 



Zone 1 [B], Pulkowa. 

 858 



