into the Rivers of Tasmania. 439 
lutely necessary that I should have all my arrangements for 
artificial spawning and breeding, &c., in order and on board 
by the 10th of that month. These I perfected, and left 
London on the 7th for Worcester, to procure the salmon 
spawn, which I/succeeded in obtaining on the 9th; and upon 
my arrival in London on the 10th, with my stock of salmon 
eggs, I found that the Columbus had got very little of her 
cargo on board, and was not likely to start for some days 
later. It was during the period of delay I was enabled to 
collect some trout spawn, from some trout out of Mr. Samuel 
Gurner, junior’s, stream in Carshalton, in Surrey, from whom 
I had obtained permission to place my salmon spawn in the 
stream, in order to keep it alive. ‘The vessel was detained 
till the end of the month, when I completed the arrange- 
ments and placed the stock on board; but even then the 
Columbus did not leaye the Dock Basin until the 38rd of 
February, and upon arriving in the Downs she was further 
detained a week by contrary winds ; so that the salmon spawn 
was thirty-three days, and the trout thirteen days, advanced 
in embryo previous to leaying England, instead of being 
that length of time on the yoyage. This it will be perceived 
is quite sufficient to account for and show the cause of the 
failure, and why the brood was bred out on this side of the 
equator ; the spawn being so far advanced, life was perfected 
much earlier as the vessel neared the warmer latitudes. 
In consequence, however, of the detention of the vessel 
in England, I had prepared for the brood coming into life 
on the yoyage, and for which occurrence I gave written 
instructions to Captain Smith for their provision. 
The usual period for incubation of salmon spawn is one 
hundred and of trout fifty days in a temperature of fifty-four 
degrees ; so that the spawn sent out in the Columbus was 
already one-third hatched, or in life, previous to leaying our 
