It is impossible for any student or observer of these animals to avoid recognition of Aristotle’s wonderfully intimate knowledge of their life-history, embryology, sexual conditions, and anatomy. When I first saw the octopus guarding her eggs the thought immediately rose in my mind,—“Aristotle must have had an aquarium!” He might have learned by observations at the sea-side, on the coast of the Mediterranean, the mode of progress of the octopus when swimming and crawling, its change of colour when excited, the form of its eggs, &c., which he has correctly described; but it is impossible that he could have so exactly designated the duration of the existence of the embryo in the egg without having had opportunities of noticing the date of its extrusion, and that of the escape of the young octopods by the rupture of the envelope. His mention of the remarkable sexual development of one of the arms, its use in the impregnation of the ova, their apparent incubation by the mother, and her incessant attention to her charge, also indicates that, during the intervening time, the male and the brooding female were continually under his inspection. We are therefore led to the conclusion that the marine aquarium, in some form, is one of the things that are not “new under the sun.” CHAPTER VIII. CUTTLES AND SQUIDS. [Illustration: Fig. 7. The common Cuttle-fish (_Sepia officinalis_), and its internal shell or “sepiostaire.”] The common cuttle-fish (_Sepia officinalis_), (often called by sailors the “scuttle”), though flabby and clammy in death, is a lovely object when alive. Unlike, the skulking, hiding octopus, but equally rapacious, it loves the day-light and the freedom of the open sea. Its predatory acts are not those of a concealed and ambushed brigand lying in wait behind a rock, or peeping furtively from within the gloomy shadow of a cave; but it may better be compared to the war-like Comanche vidette, seated motionless on his horse, and scanning from some elevated knoll a wide expanse of prairie, in readiness to swoop upon a weak or unarmed foe. Poised near the surface of the water, like a hawk in the air, the sepia moves gently to and fro in its tank by graceful undulations of its lateral fins,—an exquisite play of colour occasionally taking place over its beautifully barred and mottled back. When thus tranquil, its eight pedal arms are usually brought close together, and droop in front of its head, like the trunk of an elephant, shortened; its two longer tentacular arms being coiled up within the others, and unseen. Only when some small fish is given to it, as food, is its facility of rapid motion displayed. Then, quickly as a kingfisher darts upon a minnow, it pounces on its prey, enfolds it in its fatal “cuddle”[19] or embrace, and retires to a recess of its abode to tear it piece-meal with its horny beak, and rend it into minutest shreds with its jagged tongue. In shallow water, however, it will often rest