596 THE WONDERS OF GEOLOGY. Lect. VI. 



to us, cannot be considered as incredible or marvellous.* 

 But of all the shapes in which animal existence presents 

 itself on our globe, none are more extraordinary, or unlike 

 what is commonly conceived of living beings, than those of 

 the compound creatures which are described by naturalists 

 under the name of Zoophytes, or Animal-plants, and fami- 

 liarly known in their varied forms by the names of Corals, 

 Madrepores, Sponges, Sea-anemones, Dead-men's-fingers, 

 Sea-fans, &c. 



6. Animal nature of Zoophytes. — It was in this town 

 (Brighton) that in the year 1752, the animal nature of many 

 of the Zoophytes which abound on the Sussex coast, was 

 first established. Mr. Ellis, an eminent naturalist, was 

 engaged in forming a collection of marine plants, and having 

 occasion to examine some of the specimens through a 

 powerful microscope, he was astonished to find that the 

 Sponges, at that time supposed to be vegetables, possessed 

 a system of pores and vessels through which the sea-water 

 circulated ; and that many of the Corallines exhibited cells, 

 from which tentacula or feelers were constantly protruding, 

 and then suddenly retracting, as if seizing and devouring 

 prey. Subsequent observations have proved that the 

 substance we call sponge is the skeleton, or support, 

 of a vascular substance which invests it, and which may 

 be considered as the flesh of this animal. When viewed 

 through the microscope, innumerable pores are seen on the 

 surface of the Sponge constantly imbibing salt water, which 

 circulates throughout the mass, and is finally rejected from 

 the large openings ; this water doubtless contains the living 

 atoms that constitute the food of this zoophyte, but which 

 are so minute as to elude observation. 



The Sponges, however, approach so closely in their 

 structure to certain plants, that many eminent naturalists 



* See Thoughts on Animalcules, or a Glimpse of the Invisible 

 World revealed by the Microscope, p. 7. 



