42 New Species of Bryozoa from the Marion Islands, 



Sub-order CHEILOSTOMATA, Busk. 

 Family Catenicellid^e, Busk. 

 Genus Alysidium, Busk. 

 Alysidium inornata, n. sp. Plate I.; Fig. 1. 



Cells translucent, without ornament or appendage of any 

 kind; much elongated and tubular below; aperture oblique, 

 occupying the whole width of cell at distal end, contracted 

 internally; operculum small, oval, central; ovicells — . 

 Locality. — Marion Islands. " Challenger" Expedition. 



The cell walls are so transparent that in the living state 

 this species would afford every facility for anatomical obser- 

 vation. My specimen has ten cells ; in several the form of 

 the zooid is plainly seen, showing, however, only the closed 

 tentacles disappearing at the lower end in a small confused 

 mass of clear granular matter ; seeming to indicate an ex- 

 tremely small body of the simplest form. 



Family Bicellariad^e, Busk. 



Genus Bicellaria, Blainville. 



Bicellaria pectogemma, n. sp. Plate I.; Figs. 2 and 2a. 



Cells small, much expanded above, tubular long and 

 attenuated below; each cell arising from a short tubular pro- 

 cess on the breast of the cell below on the same side, 

 and attached to the next cell on the other side by a 

 slight expansion of the tube a little below where the next 

 cell above is given off; aperture large, wide, and square at 

 outer end, narrowing inwards ; operculum wide, and nearly 

 square above at upper and outer end; cells armed with 2-6 

 long curved spines, springing from a slightly raised process, 

 set transversely across upper end of cell and about level with 

 cell mouth ; a single (?) spine slightly curved springing 

 vertically from the centre of each cell on the dorsal surface; 

 avicularium — ; ovicell — . 



Locality. — Marion Islands. " Challenger" Expedition. 



This species is closely allied to B. grandis, Busk, but differs 

 in several important characteristics. The form of the aper- 

 ture is exactly the reverse of that of B. grandis, which is 

 widest at the inner end; the latter has never more than 

 four submarginal spines, more frequently only two, while six 

 seems to be the prevailing number in the present species. 

 The mode of attachment of the cells to each other is also very 



