Kev. T. Hincks on British Polyzoa. 215 



Lagenipora socialis^ n. sp. 



Crust whitish, granulated, of irregular figure : zoocecia 

 flask-shaped, the lower part immersed, the upper part (in adult 

 cells) produced into an erect tubular neck ; oritice circular, 

 terminal, frequently with a number of spinous processes on 

 the upper margin ; surface granular, except on the erect por- 

 tion, which is smooth : oooecia small, rounded, smootli, set far 

 back behind the tubular neck of the cell. 



Colonies forming small, rather thick, white crusts. 



Locality. Hastings, on the shells of Pecten maximus [Miss 

 Jelly). 



Suborder Ctenostomata, Busk. 



I retain in this paper the established genera ; but the 

 Ctenostomata require careful revision, and some of the groups 

 as at present constituted can hardlj be maintained. 



Genus Valkeria, Fleming. 



1. Valkeria caudatu^ n. sp. 



Stem creeping : zoocecia biserial, opposite, elongate, sub- 

 cylindrical, truncate at the top, slightly narrowed below, and 

 produced at the base into a short, pointed, caudate process j 

 disposed in companies along the creeping stem : polypide with 

 eight tentacles ; destitute of a gizzard. 



This well-marked form may be at once recognized by the 

 spur-like process below, which is very conspicuous in the 

 youngest cells. The cell is attached at a point near the base, 

 and the caudate extremity bends outwards. I have failed to 

 detect a gizzard in V. caudata ; but this portion of the struc- 

 ture is not always recognizable in preserved specimens. I 

 place it provisionally in the genus Valkeria^ hoping shortly to 

 revise the classification of the Ctenostomata. 



I am indebted to Mr. Leipner, of Clifton, for specimens of 

 this species, beautifully mounted, and showing the polypides 

 expanded as in life. 



2. Valkeria citrina^ n. sp. 



Stem erect, slender, dichotomously branched : zoocecia clus- 

 tered, somewhat spirally disposed, oval, small, and delicate : 

 clusters short, placed immediately below each bifurcation, 

 occupying about the upper half of the internode or less ; cells 

 not densely crowded : 'polypides of a citron-colour, with eight 

 tentacles, and furnished with a gizzard : shoots clustered, of 

 delicate habit, forming bushy tufts. 



