APPENDIX. No. III. 405 



of its form being distinguished ; upon moving the speck it fell 

 out of its place. 



On the iSth the embryo was indistinctly seen. 



On the 1,5th the embryo filled ^ part of the egg, but the dif- 

 ferent parts were still indistinct. 



On the 18th the body of the embryo had become larger, and 

 the covering thicker. 



On the 19th, the coverings or shells of all the eggs were more 

 or less dissolved, so much so that Mr. Hunter thought all the 

 eggs were rotting, and the whole brood of young would be lost. 



On the 20th, the young were hatched, and the shells com- 

 pletely formed. 



On the 23d, when the young snails were put in water, their 

 bodies came out of the shell as in full grown snails. 



On the 24th, they all deserted their nests. 



The specimens of the sepia found in the argonaut shell, which, 

 was caught by Mr. Cranch, in this expedition to the Congo, 

 had deposited some of its eggs in the involuted part of the 

 shell, and the animal being fortunately caught in the shell iden- 

 tified the eggs to belong to it; (PI. XIV.) they are united to- 

 gether by pedicles, like the eggs of the sepia octopus, and in 

 all other respects resemble them ; they differ from those of 

 the helix janthina and the other vermes testacea, that live in 

 water, in having no camerated nidus, and in having a very 

 large yelk to supply the young with nourishment, after they 

 are hatched. 



Upon these grounds, this animal must be resolved into a spe- 

 cies of sepia, an animal which has no external shell, and only 

 uses the shell of the argonaut, when it occasionally gets pos- 

 session of one. 



Some naturalists, unacquainted with comparative anatomy, 

 have asserted that in these eggs they saw the argonaut shell 



