SPONGES. 115 



punctures with sharp Instruments, or other modes of irrita- 

 tion. It is extraordinary that errors like these should have 

 crept into the writings of modern zoologists of the highest 

 authority, such as Lamarck, Bruguiere, Gmelin, Bosc, and 

 Lamouroux.* The notion that the sponge contracts when 

 touched is of very ancient date, for it may even be traced 

 beyond the time of Aristotle; and it has been handed down 

 by succeeding naturalists, and echoed from the one to the 

 other, so as to have gained admission, without being ques- 

 tioned, in all the recent systematic works on Zoology. 



The alleged spontaneous palpitation of the flesh, occur- 

 ring in particular parts, had its origin in the views taken of 

 the nature of sponges, by Marsigli, an Italian naturalist, who 

 in the year 1771, announced that he had seen movements of 

 dilatation and contraction in the round apertures visible on 

 the surface of sponges. This statement, so confidently ad- 

 vanced, seems to have made a strong impression on Ellis, 

 who, while pursuing a similar train of observations, came to 

 persuade himself that he could see, not only the movem.ents 

 described by Marsigli, but also the passage of water to and 

 fro, through the same apertures. He communicated this 

 account to the Royal Society in 1765; it was published in 

 its Transactions,! and will ever remain an instructive proof 

 of the degree in whicli our very perceptions may be influ- 

 enced by preconceived views, and by the force of the ima- 

 gination. Pallas immediately admitted, without examina- 

 tion, the hasty assertion of Ellis, into his '•' Elenchiis 

 ZoophytoruTYif^ whence it was copied by succeeding au- 

 thors, and the error became at length so widely dissemi- 

 nated, that for more than half a century it was received as an 

 established fact in natural history. The elaborate and accu- 

 rate researches of Dr. Grant on these subjects have at length 

 dispelled the prevailing illusion, and have clearly proved 

 that the sponge does not possess, in any sensible degree, 



• This mistaken view was adopted by Cuvier in the first edition of his 

 "Regne Animal," T. iv. p. 88; but Dr. Grant's rectification of the error 

 is noticed in the second edition of that work. — T, iii. p. 322. 



t Vol. Iv. p. 284. 



