ON THE ARGONAUT. 11 



another, it is a proof that the shell has not been made for it, 

 and does not belong to it : this part of the question being 

 one of the most important, we shall pause here a little. 



Poli, who, from what he says, must have thoroughly in- 

 spected this animal in a living state, places its great arms in 

 front, that is to say, at the anterior edge of the opening. — 

 Ferussac, who has reproduced the beautiful, but too fabulous 

 sketch of Poli, has, like that naturalist, placed it the wrong 

 way, at the same time sketching other figures in a proper 

 manner, which, on the part of one of the most ardent parti- 

 sans of non-parasitism was a serious fault; but, at least, 

 proved his candour in the discussion. However, in 1836, 

 upon some information which we gave him from Algiers, and, 

 we believe also, in consequence of some observations of M. 

 Delle Chiaje, or Yerany, he resolved to make a new copy of 

 the plate borrowed from Poli, in order to turn the animal the 

 opposite way, which is in fact the true one. It has been 

 wrongly thought that he made this change only that he might 

 not leave such weapons in the hands of his adversaries ; — 

 on the contrary, it was the result of conviction in his mind. 



It is very clear, as to the rest, that Ferussac had adopted 

 the idea that the palmated arms were to be found on the side 

 of the spiral line of the shell ; since, from 1825, as may be 

 seen by the memoir which he read to the Academy, he sup- 

 posed that the palmated portions of the gresii tentacula folded 

 themselves into a globular mass in the spiral cavity of the 

 shell, which he would not have been able to point out if he 

 had thought that these arms were in the anterior part. 



M. Delle Chiaje, whose observations will always be of 

 great weight in all questions of malacological organization, 

 has not been happy in this circumstance. In fact, he also 

 reverses the animal in such a manner as to put its membra- 

 niferous arms at the anterior part of the shell ; and manages, 

 as he can, to explain how the animal holds its shell by the 

 aid of suckers, which is difficult enough to conceive, since 

 he says at the same time, that the arms are spread out upon 

 the surface of the water. After these come Mr. Broderip, 

 who affirms^ that in a specimen which he had in his posses- 

 sion, the palmated arms were on the side of the back of the 

 shell; and Mr. James Sowerby, who nevertheless acknow- 

 ledges that in Cranch's specimen it was the contrary. 



M. de Blainville has also had well-preserved specimens 

 in his hands, and he has seen them turned in the manner we 

 have described ; nevertheless, he draws from the divergence 

 of opinions, another argument in favour of parasitism. This 

 argument ought now to fail him, and indeed the inference 



