PLANTS, AND INANIMATE MATTEE. 85 



same as the Holothouria of the Ancients, suggests that 

 Aristotle may have had in view " the large, round, sponge- 

 like algue called Spongodium, living free on the sea-bed 

 and abundant in the Greek seas." * 



Aristotle's statements about sponges are remarkable, 

 and, until the eighteenth century, naturalists do not seem 

 to have added much further information about them. Be- 

 sides giving a great deal of other information about sponges, 

 he says that they are animals resembling plants very closely, 

 because they cannot live v^hen torn avi^ay from their places 

 of attachment,! and that they show signs of feeling, a proof 

 of this being that, according to common report, they 

 contract when an attempt is made to tear them away, or 

 when the winds and waves are violent ; the people of 

 Torona, he adds, deny that this is so.t 



His conclusion, that sponges are animals, apparently 

 based on very slender data, is interesting, because natura- 

 lists were long undecided on this question. Gesner, Rondelet, 

 and Belon were disposed to consider them to be plants, Eay 

 and Tournefort classed them with plants, and Linnaeus, 

 Lamarck, Milne-Edwards, Cuvier, and many others con- 

 sidered them to be animals. It may be mentioned that the 

 opinion of Linnaeus changed, e.g., in the tenth edition of 

 the Systema NatwcB sponges are classed with plants, and in 

 the twelth and thirteenth editions, with animals. 



The assumed contractility of sponges, based on hearsay 

 evidence, but denied by the people of Torona, in Macedonia, 

 seems to have formed the chief reason why Aristotle con- 

 sidered sponges to be animals. However, sponges do not 

 seem to exhibit any such contractility, for Dr. Grant, affcer 

 numerous experiments on sponges, found no trace of it, and 

 he also says that several other investigators had been unable 

 to detect it in sponges found in many different localities. § 



There is another matter deserving of consideration in 

 connection with Aristotle's decision that sponges are animals, 

 viz., the extent to which he relied on popular beliefs. The 

 many passages on sponges, in his works, show that he 

 studied these animals in some detail, but it is worthy of 

 note that, when speaking of their showing signs of feeling, 



••= Travels in Lycia, dc, 1847, vol. ii. p. 118. 

 f H. A. viii. c. 1, s. 3 ; P. A. iv. c. 5, GSla. 

 I H. A. i. c. 1, s. 8, V. c. 14, s. 8. 



§ Edin. Philosoph. Journ., vol. xiii. 1825, pp. 342-6, vol. xiv. 182G, 

 pp. l'20-l. 



