Canadian Fossil Bryozoa. 223 



In Prof Ulrich's memoir and in this notice the various 

 forms mentioned are classified under the following sub- 

 orders and genera of Bryozoa : 



(1.) Ctenostomata, Busk. 



To which Ascodictyon of our Devonian rocks of Western 

 Ontario belongs. 



(2.) Cyclostomata, Busk. 



Including the genera Stomatopora, Proboscina, Hederella, 

 etc., from various horizons. 



(3.) Trepostomata, Ulrich. 



Including the Monticuliporoid genera, Monticulipora, 

 Prasopora, Dekayia, Callopora, Stellipora, Stenopora, 

 Amplexotrypa, Batostoma, Spatiopora, Fistulipora, Botryl- 

 lopora and allied forms from various horizons ranging from 

 the Ordovician to the Carboniferous of Canada. 



(4.) Cryptostomata, Vine. 



Including twelve families and eighty genera of which the 

 following are represented in species from Canada : Ptilo- 

 dictya, Ciathropora, Phsenopora, Graptodictya, Arthropora, 

 Dicranopora, Pachydictya, Stictopora, Coscinium, Tsenio- 

 pora, Ehinopora, Helopora, Sceptropora, Arthroclema, 

 Thamnotrypa, Fenestella, Archimedes, Phylloporina. 



(5.) Chilostomata, Busk. 



Including only three genera, as yet, of which the first 

 Paleschara, Hall, is the only Canadian form known to the 

 writer. 



Taking the forms obtained from various places in 

 Canada which are described or figured by Prof. Ulrich in 

 this volume we find the following : — 



Lower Silurian Bryozoa from Canadian rocks. 



A. — Cyclostomata, Busk. 



I. Genus Stomatopora, Brown. 



1. Stomatopora inflata, Hall, occurs in the Trenton lime- 

 stone of Ottawa, Canada. 



