REPORT ON ZOOLOGY. 237 



qiiainted with a vast number of new species, as well as established 

 several distinct genera which had not been before indicated, but 

 his classification is decidedly artificial. Adopting from the first 

 the artificial distinctions ol Polypier flexible, Poly pier pierreiix, 

 and Polypier sarcoide, he has been necessarily led, as Blainville 

 observes, to a similarly artificial arrangement of all his subordi- 

 nate groups. A better prospect has, however, opened upon us 

 in this respect. Naturalists are now guided in this department 

 of zoology by the same principles which have for some time 

 back directed their researches in the other branches of the sci- 

 ence. They see the importance of studying the entire organiza- 

 tion. And while this has led them to a close investigation of 

 the Polypi themselves in those zoophytes in which they are 

 really present, it has also led them to distinguish, and to sepa- 

 rate from these last, others, in which it is now clearly ascertained 

 that no Polypi ever exist. 



I can only make a brief allusion to a few important steps which 

 have been gained of late years in our knowledge of these animals. 

 One of these relates to the Madrepores, the animals of which have 

 been proved, by the researches of Lesueur*, Eysenhardt, and Cha- 

 misso, and more recently, as well as more decidedly, by those of 

 Quoy and Gaimard, to hold a much nearer affinity to the Actinice 

 than to the Hydrce. Blainville, who has attempted to characterize 

 the generaf from a consideration of the hard and soft parts con- 

 jointly, considers them as true Actinice, in the parenchyma of 

 which is deposited a considerable quantity of calcareous matter, 

 producing what the French call the Polypier. He observes, 

 that we may even find a gradual transition in this respect from 

 the softest of the Actinice to the most solid and most calcareous 

 of the Madreporce. He accordingly throws them both together 

 in one class {Zomitharia, Blainv.), in which however they form 

 two distinct orders. Quoy and Gaimard paid particular atten- 

 tion to the Polypiferous Zoophytes during their voyage with 

 Freycinet;}:, and ascertained the nature of the animals in several 

 genera in which they had not been described before, or only in 

 an imperfect manner. Amongst others may be mentioned the 

 Tubipora of Linnteus, which had been supposed by some to 



• Mem. du Mus., torn. vi. p. 271. 



\ Diet, des Scien. Nat., art. Zoophytes. 



X See the volume of Zoology annexed to that voyage ; also A?in. des Scien. 

 Nat., torn. vi. p. 273, and torn. xiv. p. 236. The former of the two memoirs 

 just cited contains some remarks on the supposed rapid growth of Coral Islands, 

 and the power possessed by the Polypi of raising perpendicular walls from the 

 bottom of the ocean. According to their observations, the labours which have 

 been ascribed to these animals have been very much exaggerated, and the ac- 

 counts which have been sometimes given of them altogether erroneous. 



