Chris you may like the following to either investigate further now that it has been established that Duncan jnr was born 1854. I suggest there has been a mistranscription of the year ie 3 for 5 in your family records. Easily done. The detailed information on
BISA appears to me to be submitted.
MCCALLUM Duncan, Mary
CAMERON arrived in SA 1O Jul 1840 aboard
DAUNTLESS from Greenock
Sources - 2 [McCULL
OM],7,23(2) and 41.
Passenger list and a log of the ship
DAUNTLESS which sailed from Greenock, 17 Feb 1840 with about 150 passengers for Adelaide, Port Philip and Sydney. Diary kept by James Falconer, on his way to Adelaide, then on to Melbourne.
http://www.slsa.sa.gov.au/fh/passengerlists/1840Dauntless.htm[2] Register of Emigrant Labourers Applying for a Free Passage to South Australia 1836-41, PRO CO 386/149-151 - At SA Records and may have more information about Duncan.
[7] Biographical Index of South Australians 1836-1885, SAGHS, 1986 - Info posted on the thread by Sashar.
[23] 1841 South Australia Census Returns, SAA, GRG24/13 - below
[41] B Leadbeater, South Australia Births 1836-54, Adelaide, 2010-2012
http://www.jaunay.com/census.php1.
MCALLUM Duncan
2.
MCALLUM Mrs
More information available from the author of the website, for a fee.
Sashar has given you the birth information mention in source 41.
Cheers
Cando