80 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



Fully detailed reports upon the Foraminifera of our 

 district by Mr. Siddall and others, and upon the Diatoms 

 by Dr. Stolterfoth, will be found in the volumes of 

 " Fauna of Liverpool Bay," published by the L.M.B.C. 

 The rest of the marine plants, or sea-weeds, have been 

 reported on by Professor Harvey Gibson. 



In the gallery of the Biological Station a selection of 

 the common sea-weeds of the neighbourhood will be 

 found laid out and named. 



PORIFERA (Sponges). 

 (Fig. II.) 



We all know the bath sponge, but some people do not 

 realise that it is only the horny skeleton of an animal, 

 and that there are many sponges living in our own seas, 

 some of which also form horny skeletons, but which would 

 not be suitable for domestic use because of their contain- 

 ing numerous microscopic sharp-pointed glassy spicules 

 or bristles which strengthen and protect the body wall. 



If we omit the minute and very simple unicellular 

 Protozoa, sponges are the lowest of animals. They are the 

 lowest of the " Metazoa," or animals whose bodies are 

 built up of more than one cell. All animals from sponges 

 upwards to the highest are Metazoa, so the primary classi- 

 fication of the Animal Kingdom is into — (1) Protozoa, the 

 first, lowest and simplest animals, and (2) Metazoa, all the 

 rest. Wherever there are rocks and sea-weeds you can 

 find sponges at low tide. For the most part they are 

 found on the lower surface of stones, or in crevices of 

 rocks, or sticking on the roots of large sea-weeds. Fig. 

 II. shows three very common kinds of British sponges 

 which are found almost everywhere round our coasts. 



