Objects for the Microscope. 175 



cells have a spine at each upper angle, and an appendage 

 called the bird's head. With a little management of light, 

 you will see the muscular lines by which the neck opens 

 and shuts ; when alive it snaps in all directions, seizes any 

 passing animal, and holds it fast until death. Now, as they 

 have no inward connection with the stomach of the polype, 

 neither give the food to the tentacles, it is doubtless for 

 protection that they are placed over the otherwise defence- 

 less zoophyte a sensitive and ever-ready police to keep 

 the cities of the great deep. Cities they are indeed ; for 

 examine a piece of Flustra 



FLUSTRA TRUNCATA. 



On one specimen you may count 18,000 inhabitants, all 

 rejoicing in the life bestowed upon them, and all in obedi- 

 ence and harmony performing their task in the ocean world. 

 Yes, they all have an appointed work they had it long 

 ago in the ages beyond our own existence before the 

 green earth had risen from the chaos of waters, or even 

 before the Saurian age of reptiles, in the calm clear ocean 

 of the earliest formations, the little polyzoaries of these 

 zoophytes existed, and their fossil forms are found with 

 those of the lonely Trilobite. 



It is possible to mount these zoophytes with' the polypes 

 displayed, and a more beautiful object is rarely seen. The 

 way to manage it is thus : Watch the living creature placed 

 in a shallow dish of its native element, and whilst they are 

 " out" dash in a tumbler of cold spring water, which 

 paralyses the Polypes, and they may be mounted in fluid 

 permanently. Another way I have heard, but not tried, is 

 to pour gently some spirit into the water, which irritates 

 the zoophyte, and it comes forth to drink of the intoxicating 

 fluid, and falls a victim to its poisonous influence. 



PUSTULIPORA FOSSIL, 



of which the present species are Pustulipora, Deflexa, and 

 Proboscidia ; calcareous, erect Polyzoas, with tubes half 

 immersed ; found on shells in deep water off Plymouth and 

 Zetland ; whilst the fossil slides sold by Tennant are from 

 the chalk of Kent and Wilts. 



