ON BELMULLET WHALING STATION, 153 
IIT. Quesvions or Generat Bronocy. 
1. The extinction of the larger Cetacea.—In view of the large 
numbers of the largest kinds of Cetacea which are now killed every 
year, the question of their probable extinction in the course of com- 
paratively few years must be seriously considered. ‘The case of 
Steller’s Sea-cow (Rhytina) is a well-known example of extinction pro- 
duced by excessive hunting in recent times. With a view to preventing 
this possible extinction there is some discussion as to legislation in 
Norway and England. Tt is suggested that there should be a closed 
season for the Northern Whale ‘ Fisheries ’ as in the Seal ‘ Fisheries.’ 
The serious point is that so many gravid females are killed, and it is 
impossible for the whalers to identify a gravid female, as such, while 
she is swimming in the water. Naturally, the proposed limitation of 
the whale-hunting does not meet with the approval of the whalers. 
According to them the whaling in the Northern stations will cease 
automatically before the extinction takes place. As mentioned above, 
a minimum catch of about thirty whales per steamer in the Northern 
stations is necessary for a factory to keep working at a profit. Thus, 
when this minimum has been passed, the whaling station closes down 
automatically. Tt is said that this will take place before the total 
extinction of the species on account of the minimum catch being 
comparatively high. 
The underlying idea seems to be that of a definite number of whales 
passing over a given area at one time, only a certain percentage are 
ever caught, on account of the difficulty in locating the animals and 
the chances of the chase. As the total number of animals passing 
over a given area becomes fewer, the percentage actually caught will 
fall. The conclusion drawn is that this fall will cause the minimum 
eatch per boat to be reached before the total extinction takes place. 
Tow far this reasoning is sound is doubtful, but T give it as it was 
given to me. 
The actual reduction in the number of the whales has been less 
than it might have been because the whalers only kill the larger indi- 
viduals, i.e., those over about 40 feet, as noted above. 
In the southern hemisphere there are large numbers of whales, 
which have been extensively hunted only within quite recent times. 
Against this must be put the fact that the minimum catch per boat is 
about three times what it is for the northern stations, on account of the 
greater expenses for transportation, &c., so that the question of ultimate 
extinction will probably soon haye to be considered for this region also. 
2. Migration and line of movement.—Many whales manage to keep 
an almost absolutely straight course, as if steering by a compass. How 
is this done? If their sight be good enough, it is possible that they steer 
by landmarks on the bottom, but they could only see these when diving. 
The Right whale (Balena) especially appears to have this definite line 
of movement, and it is said to keep near the shore while passing the 
Trish coast. If it be guiding itself by landmarks on the sea-bottom, it 
would be easier to do this in shallow water. If a whale be chased out 
of its course, and then left alone, the whalers say that it returns to 
