374 ANNUAL EEPOET SMITHSONIAN INSTITUTION, 191G. 



lished by Charles Frederick Holder, in Volume 15, No. 4, 1909, of 

 Country Life in America, T\-hich gives one a glimpse of the marvelous 

 beauty of some of these pirates of the deep. 



The term paper nautilus suggests the dainty structure in which the animal 

 lives at times — a fragile, involuted, vase-like object, deeply fluted and coiled, 

 the keel or edge sharp, having double points, while all over the calcareous and 

 pearly shell are deep graceful and branched radiations. The general color is 

 a delicate gray, the opening in the side of nacre, heavily coated, in sharp con- 

 trast to the horny translucent shell paper. The keel is tinted a rich brown 

 that often extends an inch or two up the side of the shell, which may be 2 

 or 8 or 9 inches across. The shell is not to be compared with the ordinary 

 covering of mollusks, as it is not essential to the animal ; it is only a dainty 

 object having the shape of a shell, formed by the animal for the protection of 

 its eggs. It is, then, a nest and in no way connected with the animal, as in 

 the case of the pearly nautilus, where the animal forms partitions as it grows 

 and is connected with them all by a fleshy pedicle or cord. The paper nautilus 

 can dart out of its fairy ship at a second's notice. 



Glancing into the shell we may see a yellow bunch of miniature grapes 

 hanging from the interior wall — the eggs — and percned in front of them is 

 the argonaut, looking very much like an octopus or devilfish. From the number 

 of empty shells found upon Santa Catalina beaches in winter and suumier it 

 might be assumed that the argonaut deserts the shell at times and lives a 

 roving, octopuslike life. 



In appearance it is one of the most beautiful of all animals as it rests in its 

 shell, trembling with color, as waves of rose, yellow, green, violet, and all tints 

 of brown are continually sweeping over it ; now irised in the most delicate shade 

 of blue, now brown or green, changing to rose, vivid scarlet, or molten silver. 

 So sensitive is it that every convulsive movement of the mantle of my paper 

 nautilus in taking water to breathe and forcing it out of the siphon caused a 

 wave of color to pass over the entire body. When the water was taken in the 

 color cells contracted, leaving it pale for a fraction of a second ; when it was 

 forced out they evidently relaxed and the entire surface was suffused with 

 color to disappear as quickly, giving a continuous heat-lightning effect. 



Of the three living specimens that I have kept in confinement one was 4 or 

 5 inches long, another 8 or 9. The small one was extremely active, leaving 

 its shell to crawl about its prison and darting back with great agility, directing 

 its funnel backward at the cluster of eggs hanging in the interior of the shell, 

 always paying the most assiduous attention to them to prevent the intrusion 

 of any parasite or enemy. 



It would recline against the weed-covered rock watching me or eyeing my 

 hand as it moved about, blushing, paling, displaying remarkable sensitiveness, 

 and when I touched the shell would protest by pumping violently, shooting 

 the shell backward and, if I held on, aiming the siphon at my hand and pump- 

 ing water at it, on one occasion filling the water with an extraordinary volley 

 or cloud of ink. But ordinarily this argonaut did not resent my friendly ad- 

 vances and when touched it would twine its tentacles about my fingers, hold 

 them closely, and rise partly from the shell, the big black and silver staring 

 eye evidently watching every movement. 



The speed with which the argonaut coiild move backward, propelled by its 

 siphon, was i*emarkable when seen from the side, but when it was observefl 

 from behind it was seen to be a perfect racing machine ; the sharp keel of 

 the shell covered by the extraordinary velamentous arms presented a perfectly 



