EAELY PALEOZOIC BEYOZOA OF THE BALTIC PEOVINCES. 



29 



BBYOZOA OF THE EHINIDICTYA BED. 



^Stomatopora arachnoidea (Hall). 

 *Corynotrypa barberi Bassler. 

 ^Corynotrypa delicatula (James). 

 Berenicea viinnesotensis Ulricli. 

 Spatiopora labeculosa Ulrich. 

 Favositella laxata Ulrich. 

 Ceramoporella inclusa Ulrich. 

 ^Rhinidictya mutabilis Ulrich. 

 RMnidictya mutabilis major Ulrich. 

 Rhinidictya mutabilis senilis Ulrich. 

 RMnidictya exigua Ulrich. 

 Phyllodictya frondosa Ulrich. 

 *Phyllodictya varia Ulrich. 

 Pachydictya fimbriata Ulrich. 

 *Escharopora suhrecta Ulrich. 

 Escharopora confluens Ulrich. 

 Escharopora ? limitaris Ulrich. 

 *Arthropora simp>lex Ulrich. 

 *Stictoporella cribrosa Ulrich. 

 Helopora alter nata Ulrich. 

 Arthroclema striatum Ulrich. 

 Arthroclema cornutum Ulrich. 

 ^ Chasmatopora reticulata (Hall). 

 Monticulipora incompta Ulrich. 

 Atactoporella typicalis prsecipta Ulrich. 

 Atactoporella insueta Ulrich. 

 *IIomotrypella instabilis Ulrich. 

 Homotrypella multiporata Ulrich. 

 Homotrypella ovata Ulrich. 



^Homotrypella hospitalis crassa (Ulrich). 

 Momotrypa intercalaris Ulrich. 

 *Romotrypa subramosa Ulrich. 

 Aspidopora parasitica Ulrich. 

 Mesotrypp, infida Ulrich. 

 Mesotrypa ? spinosa Ulrich. 

 By.thopora herricki Ulrich. 

 *Bythopora suhgracilis (Ulrich). 

 *De'kayella prsenuntia Ulrich. 

 *Dekayella prxnuntia simplex Ulrich. 

 Dekayella prsenuntia echinata Ulrich. 

 Dekayella prxnuntia multipora Ulrich. 

 *Hallopora undulata (Ulrich). 

 *Hallopora multitabulata (Ulrich). 

 Hallopora ampla (Ulrich). 

 *Batostoma magnoporum Ulrich. 

 Batostoma varium Ulrich. 

 *Batostoma winchelli Ulrich. 

 *Batostoma winchelli spinulosum Ulrich. 

 Batostoma minnesotense Ulrich. 

 Batostoma ? decipiens Ulrich. 

 ^Hemiphragma irrasum Ulrich. 

 Stromatotrypa ovata Ulrich. 

 *Trematopora ? primigenia XJlrich. 

 Trematopora ? primigenia ornata Ulrich. 

 Trematopora ? primigenia spinulosaTJhich.. 

 Nicholsonella laciiinata Ulrich. 

 Nicholsonella ponderosa Ulrich. 

 "Stigmatella claviformis Ulrich. 



The Ctenodonta bed division of the Decorah shales is scarcely 

 distinguishable from the Rhinidictya bed at most localities. In 

 Goodhue County, Minnestoa, it contains few bryozoans, but an 

 abundance of Mollusca of which species of Ctenodonta are most com- 

 mon. The few bryozoans registered from this bed show an unusual 

 percentage common to Kussia and America. 



BRYOZOA FROM THE CTENODONTA BED. 



^Corynotrypa delicatula (James). 

 ^Spatiopora. lineata incepta Ulrich. 

 ^Rhinidictya mutabilis Ulrich. 

 RMnidictya mutabilis major Ulrich. 

 Pachydictya fimbriata Ulrich. 



"Stictoporella aHbrosa Ulrich. 

 Dekayella prsenuntia echinata Ulrich. 

 ^Hallopora undulata (Ulrich). 

 Batostoma varium Ulrich. 

 *Stigmatella claviformis Uhich. 



Following the Ctenodonta bed are shales much resembling those of 

 the Rhinidictya bed, and like them, crowded with Bryozoa. Here, 

 however, the bifoliate forms are less abundant and monticuliporoids 

 predominate. Phylloporina, or, as it should now be called, GTiasma- 

 topora, is present, often in great numbers, giving the name to the divi- 

 sion. The Fucoid bed which succeeds the Phylloporina contains a 



