1! ""l Robertson: Cyclostomatous Bnjozoa. 229 



Phylum Molluscoida Milne-Edwards. 



Class Bryozoa Ehrenberg. 



Sub-Class Ectoprocta Nitsche. 



Order Gymnolaemata Allmau. 



Sub-Order II. Cyclostomata Busk. 



Gymnolaemata with calcareous, tubular zocecia possessing a 



plain, inoperculate orifice. Ova matured in special chambers 



called ooecia, or ovicells which arc sometimes modified zocecia, 



sometimes inflated portions of the surface of colony or internode. 



Crisiidae Husk. 



Les Crisics Milne-Edwards, 1838. 

 Crisidae d'Orbigny, 1850-52 

 Crisiac Smitt, 1865. 

 Crisiidae Busk, 1875. 

 Crisiidae, Hincks, 1880. 



Zoarium dendroid, calcareous, composed of segments united by 

 corneous joints. Zocecia tubular, disposed in one or two series. 

 Ocecium an enlarged zooecium. 



As in the preceding papers of this series, the classification 

 and method used by Hincks ('80) have been adopted wherever 

 possible, together with synonymy, and in many cases diagnoses, 

 with such changes as the present state of our knowledge demands. 



Crisia (part) Lamouroux. 



Sertuhiria (part) Linnaeus, 1758. 



Cellularia (part) Pallas, 1766. 



Cellaria (part) Ellis and Solander, 1786. 



Crisia (part) Lamouroux, 1816. 



Crisia, Millie-Edwards, 1838. 



Crisia, d'Orbigny, 1850. 



Crisia, Smitt, 1865. 



Crisia, Busk, 1875. 



Crisia, Hincks, 1880. 



Crisia, Harmer, 1891. 



Zocecia in a single series or in two alternate series. 

 The genus Crisia is easily identified by the shape and arrange- 

 ment of its zocecia. The whole number of species falls into two 



