41 



Thompson, D'Arcy W., 1879. New and Rare Hyd. Zooph. 

 from Australia and New Zealand, A7in. Mag. Nat. Hist. (5), 

 vol. iii. 



Explanation of Plate. 



Colonies of Scrtularia elongata picked up in the North Sea (slightly reduced). 



The central thicker and whiter rod is tlie twig over which the hydro- 

 rhiza of the colonies ramify, the whiteness being due to an encrusting 

 polyzoon layer. 



