1904.] on the Progress of Marine Biology. 549 



These alternations repeat themselves, sometimes for several hours con- 

 secutively, almost on the same spot, with occasional pauses, which 

 seem to be those of repose. It is when the cetaceans appear in this 

 way at the surface that the nearest whale-boat should make every 

 endeavour to come up with them before they again disappear, and so 

 soon as one of them gives a sufficiently good presentation of the 

 part of its body near the head, the harponeer fires his shot. But 

 this critical moment seldom arrives until after several hours of pur- 

 suit, even when the animals are full of confidence and allow the 

 whalers to get well in amongst them. Most frequently, and under 

 the most favourable circumstances, it happens that during the three 

 or four seconds which the emergence of the animal at each of his 

 eight or ten respirations lasts, the presentation is bad, or the move- 

 of the sea has destroyed the aim ; it is then necessary to wait till 

 after the next sound. 



If the animals signalled pursue a fixed route with any speed, it is 

 useless to attempt the attack ; it is impossible to come up with them 

 because they are then on passage. Once I followed a large Balin- 

 oj/tera for six hours with my ship. He travelled about thirty miles 

 in an absolutely straight line, which shows that the marine animals 

 possess a sense of orientation more remarkable than that of the 

 migratory birds, because these can always see the ground above which 

 they travel. 



At last, close to the boat, a powerful blow like a jet of steam 

 comes out of the water ; the back of the animal emerges immediately 

 afterwards ; in the movement necessary to recover the horizontal 

 position of its head, the dorsal fin appears and finally the lumbar 

 region, which is much curved by the action of the tail, which deter- 

 mines the descent. It now proceeds for several lengths, hardly 

 submerged, wliilst the steersman, who can see the lighter-coloured 

 portions of this immense body, and sometimes a certain motion of 

 the dorsal fin, steers the boat, driven by all the force of its crew, so 

 as to cut the route of the cetacean. A fresh blow cuts the water, a 

 black back presents itself at a distance of five or six metres, the shot 

 is fired, and the eye can follow the harpoon with the attached line. 



But at the first moment there is nothing to show that the animal 

 has been touched. In a body of such size the arrival of sensation in 

 the brain and the transmission of the will to the periphery require a 

 sensible time. The success of the harponeer is indicated by the 

 rapid running out of the line, which very soon produces heat and a 

 dense smoke in the bollard round which a turn is taken in order to 

 allow the harponeer to regulate the run of the line according to the 

 velocity of the cetacean and the direction which it follows. This is a 

 very delicate moment for the safety of the whaler ; nobody moves, 

 and the turns of the line, carefully coiled in a receptacle, run out 

 without a check. A second whaler approaches in order to take the 

 end of this line, when it is apparent that the thousand metres in the 

 first boat will not be sufficient, and to add it to his own line. The 



