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rRANSA< riONS LIVERPOOL BIOLOGICAL SOCIETY. 



Polyzoa. Some are erect branched colonies (see fig. XI., 

 1 and 4) like Zoophytes, from which they can only be 

 distinguished by the microscope; others are flat and 

 incrusting (No. 3), and have a limy covering so as to be 

 quite hard and brittle; some of the colonies form net- 

 works extending for many square inches over the surfaces 

 of stones and the blades of the great brown oar-weed. 

 Fhistra, the " sea-mat " (No. 1), is frequently found cast 

 up amongst sea-weeds. A small piece is shown magnified 

 at 2. Bugula (No. 4) is usually obtained by dredging; 



Fig. XI., Polyzoa (1, 3 and 4 natural size, 2 and 5 magnified). 



part of the colony, alive and expanded, with polypites and 

 " birds-head " processes, is shown at 5. Forms like 

 Lepralia (3) are found under stones and on shells in rock 

 pools. Specimens of these and other kinds of Polyzoa are 

 generally to be seen in our tanks at the Aquarium, but in 

 order to see their minute structure and wonderful beauty 

 the microscope is required. The reports in our " Fauna " 

 are by Miss L. R. Thornely. 



