3298 THE MOLLUSKS OR SHELLFISH 



distinguishing features of the species. Although we usually speak of the octopods 

 as shell-less or naked mollusks, an indication of an internal shell is present, in the 

 form of two short styles, embedded in the tissues of the mantle. These mollusks 

 are solitary creatures when adult, but they are said to herd together in small com- 

 panies when young. They live in the fissures of rocks, or hide away beneath great 

 bowlders. When they walk or creep, they elevate the sack-like body above the 

 head, and progress slowly upon the extremities of the arms, which are a little curved 

 near the tip. They can creep in any direction, but they prefer a side- way move- 

 ment. On the contrary, if their progress in walking is comparatively slow, this is 

 compensated by the rapidity of their movements when swimming. Body foremost, 

 with the arms stretched beyond the head, they dart backward with great rapidity, 

 being propelled by the successive expulsions of water through the funnel. The 

 arms are also made use of in swimming, and those which are provided with an ex- 

 tensive connecting web are the most effective swimmers. None of the octopods 

 ever attain such enormous dimensions as some of the decapods, still some would be very 

 dangerous foes to cope with beneath the water. Mr. J. K. Lord saw the arm of an 

 octopus, captured at Vancouver island, which measured five feet in length, and was 

 as thick as his wrist; and M. Verany has given an account of a specimen which 

 measured three metres from tip to tip of the outstretched arms. In the account of 

 the mollusks, obtained during the voyage of the Samarang, Mr. Adams observes : 

 ' ' Octopi of enormous size are occasionally met with among the islands of the Meia- 

 co-shima group. I measured one, which two men were bearing on their shoulders 

 across a pole, and found each arm rather more than two feet long, giving the crea- 

 ture the power of exploring an area of about twelve feet without moving, taking the 

 mouth for a central point, and the extremities of the arms to describe the circum- 

 ference. ' ' 



In 1872 a very large specimen was stranded on the beach in the Bahamas, the 

 arms of which were five feet long, and the weight was estimated at two hundred to 

 three hundred pounds. The eggs of the Octopus vulgaris when first laid are small, 

 oval, translucent granules, resembling grains of rice, not quite the eighth of an inch 

 long. They are fixed along and around a common stalk, to which every egg is 

 separately attached. These clusters vary in length according to the condition or 

 age of the parent; those produced by a young octopus seldom exceeding three 

 inches in length, and from twelve to twenty in number; but a large, full-grown 

 female will deposit from forty to fifty of such clusters, each about five inches in 

 length. In each of these clusters Mr. L,ee counted about a thousand ova, so that a 

 single octopus may produce at one laying a progeny of from forty to fifty thousand. 

 The mother octopus watches, tends, and guards the egg clusters for about fifty 

 days, when the young emerge from the capsules. The sexes differ scarcely at all 

 externally, but at the breeding season a curious modification in the third right arm of 

 the male is noticeable. It becomes swollen, and from it a long worm-like process is 

 developed, furnished with two rows of sockets (the Hedocotylus) . From the end of 

 this process extends a slender, elongated filament. When its owner offers his hand 

 to a female octopus, she not only accepts it, but keeps it, for this remarkable out- 

 growth is then detached from the arm of her suitor, and becomes a moving creature, 



