76 REPOKT 1844. 



right (No. 6). This clearly shows they must have been much hurt. In the inside 

 of the shell No. 5, it may be observed, that the poulp repaired its shell with two 

 little morsels of the same, which, in cutting it, I left within. The poulp is very 

 clever, but with all its ingenuity could not succeed in properly placing the bits, as 

 this specimen shows. 



"October 29th. — I broke from a shell a piece of the length of eleven lines, exactly 

 where the dark spots are situated on the keel of the Argonaut, to ascertain whether 

 in repairing it the spots would be reproduced. The shell was no sooner broken than 

 the poulp spread its membranes over it, and in this manner swam about, ate, and did 

 not uncover its shell till the reparation was completed. Three hours after the break- 

 ing I took up the Argonaut with my net, and the keel was mended with a fine skin, 

 on which the rudiments of the spots were visible. (See specimen. No. 7.) This 

 experiment proves clearly that the reparation is effected by transudation from the 

 membranous arms of the Cephalopod." 



The letter then proceeds to detail observations on the different rate of growth of 

 the young Argonauts which are excluded from the egg whilst within the cavity of the 

 spire of the parent shell, where they are protected for a time, as in a marsupial pouch, 

 and the escape of the young at successive intervals from that nursery. " To ascer- 

 tain whether the young Argonauts after exclusion from the egg could live without 

 the aid of the parent, I made the following experiments : — I took a number of them 

 which had been born two days before and put them into a large glass vessel filled 

 with sea- water and covered with muslin, through which the water could have ingress 

 and egress without allowing the young Argonauts to escape ; I put the vase into a 

 basket, to which I suspended a piece of iron to make it fall to the bottom of the cage. 

 The next day they were all dead. I repeated the experiment, detailed in my first 

 memoir*, to ascertain whether the ova could be developed without the aid of the 

 parent ; it was on the same plan as the preceding with regard to the small polypes. 

 In twenty-four hours after removal from the spire of the parent shell the eggs had 

 enlarged to double the size they were when put into the vase, and in eight days no 

 vestige of them remained ; they had evidently decayed and been dissolved. I doubt 

 not, therefore, that the parent Argonaut attends to the preservation and development 

 of the eggs within the spire, and preserves them with some gelatinous or mucilagi- 

 nous matter from the contact of the sea-water." Madame Power then states that 

 having examined at least 600 specimens of the Argonaut in the course of her inquiries, 

 she had not once discovered a male specimen, but that all had eggs adhering in greater 

 or less quantity to the involuted spire of the shell : the accomplished naturalist con- 

 cludes by observing, " From this great quantity of Argonauts, from very young spe- 

 cimens to those of full size, you may see that I have endeavoured to omit nothing 

 that could elucidate those interesting points noted by you. I am sorry that this 

 year, in consequence of the bad weather, I am not able to put before you the young 

 Argonauts developed as far as the beginning of the fabrication of their shells : I hope 

 in future to be more fortunate. I must also add, that having several times wished to 

 repeat my observations on the fate of the Cephalopod of the Argonaut, when taken 

 out of its shell, the result has been that they sometimes, with difficulty, replace them- 

 selves in the shell, but that, if the shell be removed, they do not form another, but die 

 in consequence. And I assure you that the Cephalopod of the Argonaut is the most 

 difficult of marine animals to study from its extreme delicacy', and that out of 100 ex- 

 perimented on, not more than fifteen survived. It now only remains to me to render 

 you most sincere thanks, and to profess myself most grateful for your instructions 

 and for the pleasure you have given me in satisfying in any degree your wishes. 



(Signed) " Jeanette Power." 



" Messina, 30th January, 1840." 



The second Memoir, entitled ' Continuation of Observations on the Polypus of the 

 Argonauta Argo, in 1839,' contains a more detailed account of the experiments re- 

 counted in the foregoing letter, with additional observations. The relative position 

 of the animal to its shell is always the same : when retracted the visceral sac is 

 lodged in the spire, the membranous arms to the right and left, the other six arms 

 placed beneath the body in the middle ; the mouth in the centre of the large aperture 



* Trans. Acad. Giaenian, vol. ix. 1824. 



