606 



THE WONDERS OF GEOLOGY. 



Lect. VI. 



The body of the animalcule consists of a transparent sac 

 or pouch, doubled on itself, and having at the mouth, or 

 large external opening, ten or twelve tentacula fringed with 

 cilia, which have the power of extending and contracting 

 with great celerity. 



Lign. 133. — Polype of Flustra pilosa ; with its mouth and ciliated 



arms protruded from the cell. 



(Magnified 150 times.) 



The Flustrae present considerable variety in the form 

 and arrangement of their cells. The most common 

 species are found attached to marine plants, which they en- 

 close, as it were, in a living sepulchre (PL V. Jig. 5) ; 

 others spread into foliated expansions, and have both sides 

 covered with cells.* The prevailing hue is white, or a 

 light fawn colour, but some species have a tinge of pink or 

 yellow. They abound in every sea, and are not restricted 

 by climate, occur in profusion along the sea-shores, and are 

 found attached to the fuci that are thrown up from the pro- 



Celullar Polypes. The observations were made at Brighton, and I had 

 the pleasure of seeing the live zoophytes under the fine instrument 

 constructed by Mr. Lister. 



* See Dr. George Johnson's beautiful work on " British Zooph 

 for numerous figures and accurate descriptions of the British Flustnc, 

 &c. 



