This Spears Games Nursery Rhyme Jigsaw set reminded me of some of the jigsaws I had as a very young child. The artwork is particularly nice and while some pieces are missing, the set is complete with the box and each jigsaw has a sample picture to help during assembly.
The Spears Games jigsaw that matches the front of the box. I did a quick search for Spears Games and I think this is the best site for more information.
The box itself is not dated but the Made In England logo says that it must be post 1932 when the German company opened its' UK factory. However, I'd guess at 1950's - 1960's being a more likely date for this item.