EUCRATEA CHELATA. 15 



species is often decumbent. A few cells are repent and 

 adnate ; and from these the erect shoots arise, and the 

 zoarium then assumes its normal condition. But in the 

 remarkable variety a the decumbent mode of growth 

 seems to be permanent. I first met with it in the Isle of 

 Man, where it is common, spreading in rather large den- 

 dritic patches over oyster and other shells. In this con- 

 dition the species curiously imitates the habit of Hippo- 

 thoa, Lamx., and sends off branches from the sides of the 

 cells. 



Large, much-branched specimens frequently occur, 

 which show no tendency whatever towards an erect 

 growth, but seem to have taken on in permanence the 

 characters of the last-named genus. So completely are 

 the habit and aspect of the Polyzoon changed in this 

 repent variety, that it is difficult to recognize it under its 

 disguise. There are generally, however, a number of the 

 tubular processes rising below the aperture which are 

 so characteristic of Eucratea chelata. In this variety the 

 cell is often much produced below, and the aperture is 

 less distinctly marginate than in the erect form. 



Smitt has noticed that in Norwegian specimens of the 

 normal habit this character is, as a rule, much less strongly 

 marked than it is in English examples. In beautiful 

 specimens from Australia, where E. chelata is abundant, 

 the raised border is highly developed ; the cells are large, 

 of most delicate texture, vitreous, transparent, and glossy ; 

 the whole aspect of the species has changed under the 

 genial influences of its southern habitat. 



The variety gracilis is of extremely delicate habit ; 

 and the portion of the cell below the aperture is cyKn- 

 drical and very slender. The upper part, also, has much 

 less breadth than in the normal form ; and there is no 

 longer the striking resemblance to a horn. 



