BRYOZnA. 397 



is sometimes represented by a row of strong tubercules. Such 

 species approacli Fenextralia Prout. 



Original type: P. dendroides McCoy; accepted type: P. schn- 

 murdi Prout. Range. Niagara to Coal Measures. 



THAMNisrrs King. Zoaria differing from those of Polrpora, 

 in wanting the dissepiments entirely, or in having them recur 

 at very irregular and much longer intervals; besides, the branches 

 bifurcate more freely. 



Type: T. dubius Schlotheim sp. Range Niagara to Permian. 



PHYLLOPORA King. Zoaria infundibuliform, consisting of an- 

 astomosing branches, which form a regular, round-meshed net- 

 work. Zooecia in two or more rows. 



Type: P. ehrenbergi King. Range. Devonian to Permian. 



(?) CRYPTOPORA Nicholson. May be the same as Henritrypn. 

 PTILOPORINA Hall. 

 PTILOPORELLA Hall. 

 (?) LOCULIPORA Hall. 



Family ACAXTHOCLADIHXE Zittel (Ulrich emend). 



Zoaria poriferous on one side only, dendroid, pinnate, or 

 forming feuestrated expansions; consisting of strong central 

 stems and numerous lateral branches which proceed from their 

 opposite margins. The lateral branches are free, or may unite 

 (in the feuestrated genera) with those of the adjacent branches. 

 Non-poriferous dissepiments absent. Zoupcia and minute charac- 

 ters as in the FEXESTELLID.K. 



PIXXATOPORA Vine. (Glauconome of authors) Zoaria small 

 and delicate. Lateral branches short, free. Cells in two rows, 

 one on each side of a moderately developed median keel, which 

 is fainter or wanting on the lateral branches. 



Type: Glauconome elegans Y. & Y. Range, Lower Helder- 

 berg to Upper Coal Measures. 



SEPTOPORA Prout. Zoaria feuestrated, flabellate or leaf-like. 

 Primary branches numerous, increasing by bifurcation or inter- 

 polation, and so arranged that the smaller lateral branches 

 which proceed from their opposite margins unite with those of 

 the adjacent brandies. Reverse, or non-celluliferous side usually 



