James and William HOOKINS (Tree T)

James and William HOOKINS were 2 of the 10 children of Henry and Maria HOOKINS who come from the same village in North West Somerset as my own family but I do not yet have evidence of their link to that family. In the 1861 Census James and William disappeared from the family unit which is not unusual because they were both Agricultural Labourers so it is quite likely that they could be at the place of their employment. However they did not seem to appear anywhere else. At that time they would have been 24 and 22 years old respectively. I have now located them on the passenger list of the Barque "Caucasian" (seemingly as emigrants) leaving Southampton on 10th Sep 1857 and arriving in Adelaide South Australia on 26th Dec 1857. About 200 people made the journey and unlike other journeys it is good to know that no deaths occurred on the voyage. I wonder what happened to them?