198 THE PAPER NAUTILUS. 



agitation of the waves. This sailing is not, however, of long 

 continuance, for having taken in all their tentacles, they 

 upset their boat and so return to the bottom. 



Until a comparatively recent period, very little was 

 known of the nautilus ; for, although shells were plentifully 

 found on the shores of the warm seas it inhabits, the fish 

 itself, living chiefly at the bottom of the sea, creeping like a 

 snail, or lying in wait for runaway crabs or suchlike food, 

 was difficult to obtain. However, a specimen was captured 

 by Mr. Bennett, a naturalist, at the New Hebrides, and the 

 great naturalist. Professor Owen, described the fish in a 

 valuable memoir. The specimen is still preserved in the 

 museum of the Royal College of Surgeons, in London. Little 

 could be known from the shell itself; but here was the tiny 

 navigator of the ocean, that would ride out a storm in which 

 the strongest man-of-war might founder, revealed in all its 

 most curious mechanism: the oars and aerial sails — disap- 

 pearing, to give place to its real method of propulsion. 



The Paper Nautilus has eight tentacles, and one pair of 

 these expand at their extremities into broad and thin mem- 

 branes, which compose a web of several sorts of fibres, inter- 

 woven for the wrapping up of some parts, the fibres giving 

 them an elasticity by which they can contract and grasp the 

 parts they contain — whence the fable received through so 

 many ages, of its sails ; the membranous arms of the fish are 

 the organs for secreting and repairing the shells. 



The functions of the supposed sails of the paper nautilus 

 were determined by an experiment. One of the " sails " was 

 cut off in several living specimens, the right sail being 

 removed in some, the left in others ; and the creatures were 

 then kept in a submarine cage, and supplied with food. 

 Some of them survived the operation for four months, when 

 it was found that the shell had grown only on that side on 

 which the membranous arm had been preserved ; thus show- 



