BRYOZOA—TREPOSTOMATA. 



135 



XLI. CoNSTELLARrA. Dana. 

 Erect, flattened branches or fronds from an attached basal ex- 

 pansion ; surface with depressed stellate maculae, the spaces be- 

 tween rays elevated and bearing two or three short rows of closely 



Fig. 190. a, Petalolrypa compressa, tangential sections with few, and with many meso- 

 pores, a' f , vertical section, X 9 > ^> Dekayella praenuntia, b / , var. echinaia, surface 

 X \Yz \ b n ', var. multipora, thin- walled, small acanthopores, X 9 '■> b f// , same, thick- 

 walled, large acanthopores, X 9 > ^ iv > same, X 2 5 > ^ v > same, vertical section, X 9 > 

 c, Dekayia aspera, tangential section, X 9 '■> d, Batostomella spinnlosa, X Y^-> an d ver- 

 tical section, tangential section and surface, X 9 '■> e t Bythopora herricki, X 4/^ '■> f\ 

 Eridolrypa mutabilis, surface, X A l A '■> g, Stenopora carbonaria, vertical section, X 9 > 

 h, Constellaria varia, surface, X 4-K » /> Batostoma winchelli, surface, X A/4. an< 3 X 9 

 k, B. fertile, var. circtdare, surface, X 9 > A Hemiphragma tennimurak, surface with 

 incomplete diaphragms, X 4-X '■> I', P art of vertical section, X 9 '■> m , Stro?natotrypa 

 ovata, surfaces of two different layers (m f and fn // ), X 9 > n i Callopora multitabulata; 

 n', surface, X 4/^ 5 w// > surface showing zooecial covers, X 9 '■> « /// » vertical section, 

 X 9 ; 0, Nicholsonella pulchra, surface X \ l /z- (All after Ulrich.) 



approximated apertures; mesopores aggregated into maculae with 

 crowded diaphragms. Ordovicic. 



