406 



POLYZOA HYPPOCREPIA. 



Hob. Lough Erne, found in September 1837, W. Thompson. 

 Discovered in the Grand Canal near Dublin, in October 1842, G. 

 J. Allman. 



Polypidom entirely membranous, 

 confervoid, filiform, diffusely and 

 irregularly branched, of an olive- 

 green colour, consisting of a single 

 series of cells, catenated together 

 and separated only by a joint at 

 their origins : cells oblong, narrow 

 at the base and widening upwards, 

 smooth and even, semipellucid, the 

 aperture subterminal and lateral, 

 forming a short narrow tube with 

 an even rim. 



This singular zoophyte has been 

 well figured and described by Pro- 

 fessor Allman. The polype is as- 

 cidian, and appears to have a 

 crown of about twenty-six ciliated 

 tentacula arranged in an uninter-" 

 rupted circle. Professor Allman 's 

 paper in the Proceedings of the 

 Royal Irish Academy, is printed 

 as a separate pamphlet with the 

 title " On the muscular system of Paludicella articulata, and other 

 Ascidian Zoophytes of fresh water." Dublin, 1843. 



