INTRODUCTION. XIII 



by pores, not by roots, as we learn from Fuci. 

 As Zoophytes, are, many of them covered with 

 a stony coat, the Creator has been pleased that 

 they should receive nourishment by their naked 

 flowers. He has furnished each with a pore, 

 which we call a mouth. All living beings enjoy 

 some motion. The Zoophytes mostly live in the 

 perfectly undisturbed abyss of the ocean, they 

 cannot therefore partake of that motion which 

 trees and herbs receive from the agitation of the 

 air. Hence the Creator has granted them a 

 nervous system, that they may spontaneously 

 move at pleasure." Ellis, iiowever, was not to 

 be shaken, he still retained his previous opinions, 

 which, with the exception of those on the cal- 

 careous Corallines, are those now received as 

 true. As these points will be considered when 

 the different orders ])ass in review, it will not be 

 necessary particularly to notice them here ; but a 

 careful examination of the observations scattered 

 through the following pages will certainly con- 

 vince the student of the truth of Ellis' views, 

 however plant-like the productions may seem. 

 The system of arrangement which has l)een 

 followed is the one proposed liy Dr. Ct. Johnston 

 in his work on British Zoophytes. In principle 

 it is certainly more natural than any hitherto 

 proposed, though it is open to a few objections. 

 By making a polype to be an essential character 

 of the Class, it therel)y excludes some animals 

 of still lower station, which by former Authors 

 were united together. In the systems of Linnaeus, 

 Cuvier and many others the calcareous Corallines 

 and Sponges are arranged with the true Corals, 

 but in Jolmston's they are excluded. The cal- 

 careous Corallines are, however, now generally 

 admitted to be purely vegetable; but thougli of 

 late, some doubt has been expressed about the 



