528 M. SANDER RANG 



It seemed to us that we were at that instant enjoying an es- 

 pecial good fortune that we only owed to chance, and which 

 no naturalist had enjoyed before us. 



Many days' experience however, proved to us that it was 

 no particular good fortune ; for the poulps that we were 

 watching all presented to us the same fact, and that inva- 

 riably ! 



In order to be better understood, and to leave no doubt as 

 to the position which this mollusc presents in the shell where 

 it is constantly found, we will give a fresh description of it, 

 following, step by step, that which has been the most perfect 

 of our experiments. 



The poulp with its shell, lying motionless at the bottom of 

 the vase in which we had just placed it, struck us first by the 

 brilliancy and richness of its hues, which our sketch is far 

 from conveying. It was little more than a shapeless mass 

 that we had before our eyes ; but this mass was all silvery, 

 and a cloud of spots of the most beautiful rose colour, as well 

 as a very fine dotting of the same, heightened its beauty. A 

 long semicircular band, of a vivid ultramarine blue, which 

 melted away insensibly, was very strongly marked at one of 

 its extremities ; l the shell was nowhere visible, but with a 

 little attention we could easily recognize its general form, and 

 we could even distinguish some grooves of its surface, as well 

 as the tubercles of the keel. A large membrane covered all, 

 and this membrane was that of the arms, which so peculiarly 

 characterise the poulp of the argonaut. The animal was so 

 entirely shut up in its abode, that the head and the base of 

 its arms were very little raised above the edges of the open- 

 ing of the shell. On each side of the head, between it and 

 the partition wall of the shell, a small space left free allowed 

 the eyes of the mollusc to see what was without, and their 

 sharp and fixed gaze appeared to announce that the animal 

 watched attentively what was passing around it. The slen- 

 der arms were folded back from their base, and inserted very 

 deeply round the body of the poulp, in such a manner as to 

 fill in part the empty spaces which the head must naturally 

 leave in the much larger opening of the shell. Of these six 

 arms, the two lower 2 (or abdominal) ones descended on each 



1 This band of ultra-marine blue is represented in the drawing which 

 M. Rang has given as extending from the bases of the palmated arms of 

 the poulp, along the course of the keel of the shell for about half its 

 length. — Ed. 



2 To conform to custom, but without admitting the correctness of the 

 principle, we designate the membraniferous arms as being superior, that 

 is to say on the dorsal side, and the two opposite arms as being inferior. 



