The Fruit Knife, like other knives, came in solid and hollow handle. Both are shown here. It interesting, like with the spoons, some patterns differentiate between different fruit. For example here in Imperial Queen by Whiting there is a Fruit Knife and an Orange Knife, which are clearly two different pieces of silver.
(Fruit knife shown in Louis XV by Whiting 6 inches)
(Fruit Knife shown in Imperial Queen by Whiting 6 inches)
(Orange Knife shown in Imperial Queen by Whiting 6 1/2 inches)
(Fruit Knife shown in Blackberry Vine by Tiffany 7 3/4 inches serrated)
(Fruit Knife shown in Blossom by Dominick and Haff 6 3/4 inche serrated)