"MUSTER ROLL FOR MILTON ABBOT PARISHE IN THE HUNDRED OF TAVISTOCK"
G followed by a number written after an owner's name refers to the valuation of his or her property - in the case of G 7 this was between £10 and £20*. (*value as in 1569).
Cors, short for Corselet, and Scull are items of body armour - respectively, a toughened leather shirt or one made of chain which covered the upper body and a steel cap worn under an ordinary hat to give protection to the head.
Caliver was an early gun similar to a harquebus.
A properly-made 16 foot Pike with steel tip etc. was used to unseat a man from his horse.