12 BROOKLYN Ml'SEl'M SCIENCE BULLETIN 3. I. 
a habit of ejectiuii; indigestible material such as most sharks frequeutlv 
swallow. 
During the cruise of the Daisy, two or three blue sharks, about 
se\-en feet long, and a smaller shark of a different kind, appeared under 
the vessel's stern on the day on which a sailor died. The old, old, 
maritime conviction that these hated brutes had come exjiresslN- for the 
body was breathed about the ship ; but it was noted i)articularl\- that the 
sharks paid no attention when the dead man was consigned to the waters, 
and they followed uninterruptedly in our wake for several days after we 
had resumed our course. No doubt sharks, like certain sea birds, are ajit 
to follow a whaler more regularly than a merchant ve.ssel, for the former 
is an oleaginous craft, sometimes leaving a slight "slick" in its track, 
and always, if the whaling has been successful, appealing to another 
.sense than sight and hearing. The acuteness of the olfactory .sense in 
birds is a matter of conjecture, but in sharks it is known to be highh- 
developed, probably replacing altogether the sense of taste. 
Tropical sailors sometimes cut out the cruml)ly, lim\- otoliths of the 
blue shark and other sj^tecies, and use them as a kind of specific in the 
primitive therapeutics of seafarers. They also use the vertebral disks of 
the shark's spine to make laminated walking .sticks. Rarely the white, 
firm flesh is eaten, though prejudice acts again.st this, and the average 
sailor would prefer to feed on half- rancid salt meat until he died of 
the .scurvv. In general, therefore, the sole reason for catching a blue 
shark is to kill it and pitch it back into its element. 
We cannot clo.se an account of the blue shark without referring to 
its frequent le.s.ser companions, the remora and the pilot fish. The former 
clings by a sucking disk on its head, thus a\-oiding the effort of swim- 
ming, and subsists upon the scraps and crumbs from the shark's table. 
The writers have .seen as many as four remoras attached to one blue 
shark. Sometimes the\- cling to the under surface or flanks of their 
ho.st, sometimes they lie belly up on the donsal side of the shark's pectoral 
fins, and although frequentl\- shifting their positions, they are nevertheless 
so tenacious that they often may be drawn onto the deck of a shi]i with a 
captured shark. 
The little .strij^ed pilot fish, of which man> fanciful tales are told. 
accomi)anies the shark either singly or in small .schools. The junior 
writer once saw the mate of the Daisy hook a blue shark, hoist it half out 
of water, and after lashing the squirming mon.ster in that jxisition, angle 
successful! v for one after another of the .seven pilot fish which swam 
