It having been seen that many of the eggs left in their original position had been bruised by the mother octopus, and that there were black marks on the stone beneath them, betokening the presence of decomposition, I was anxious to remove the remainder from her; but, for the reason above mentioned, amongst others, I considered it would be prudent to assure myself that the eggs transferred to the smaller tank retained their vitality. Seeing, at the expiration of four days, that the young animals within them were as lively as ever, and progressing so rapidly that their escape from the egg might soon be expected, I had the larger tank partly emptied again, for the purpose of taking from the nest any that might still be uninjured. It was found, however, that those which had not been torn away by the parent had been squeezed by her between herself and the rock-work, and were consequently dead, only a very few showing signs of having been prematurely hatched by the violent rupture of the envelope. She had overlain her babies. Those which were taken from her on the forty-second day from their extrusion for special inspection, were successfully hatched, and I do not doubt that if they could have been kept clean and free from parasites this would have taken place if they had been detached immediately after they were laid. The young octopods made their appearance on the 8th, 9th, and 10th of August: the eggs had been extruded on the 19th, 20th, and 21st of June, and thus, although it was proved, as I expected, that the development of the embryo does not depend on incubation, the accuracy of Aristotle’s statement that its period in the egg is fifty days was completely and satisfactorily confirmed.