G4> 



BICELLARIIDiE. 



Family IV. — Bicellariidae. 



BlCELLAUIAD^K, Busk. 



BiCELLARiE^, Sraitt. 



ZocEciA rather loosely united in two or more series, or dis- 

 junct ; ohconic, or hoat-sliaped, the aperture usually 

 occupying a large proportion of the front. Avicularia, 

 when present, capitate, pedunculate, and jointed. Zoa- 

 RiuM not articulated, erect, and phijtoid, or composed 

 of a number of cells connected by tubular processes. 



The zoarium assumes two very different and strongly con- 

 trasted conditions within tlie limits of this family ; and it 

 is only after carefully examining the entire series of forms 

 included in it that we recognize the close affinity of such 

 divergent genera as Bicellaria and Beania. 



The two are connected and linked together by the genus 

 Bugula and the genus Diachoris, of which latter we have 

 no representative on our coasts, but which occurs in the 

 Mediterranean. 



In Bicellaria the cells are widest above, and taper off 

 very decidedly below. The inferior subtubular portion is 

 generally much produced, and occupies a much larger pro- 

 portion of the whole than it does in the genus Bugula. 

 The aperture is usually ample, though not so large as 

 in the last named; it 



narrows downwards, and 

 is slightly pointed below 

 (woodcut, fig. 1) . The cells 

 are so placed that the lower 

 extremity is directed in- 

 wards towards the median 

 line; and this is also the 

 case, though to a less ex- 

 tent, in the genus Bugula. 



Fig. 1. 



Bicellaria (Australian). 



