Thank you for your input, Jim.
First thing is to confess that i don't read any book thoroughly; i page them now an then and consult them when i need ... thus finding new stuff each time i open them.
But trying to link to your notes ...
I would rater put in separate sentences that: A-Plug bayonets in Britain were basicaly used by military. B-Plug bayonets with undulating blades are mostly affected to British typology. One thing does not oblige for the other (syllogism ?)
Agreed that, this type of bayonet, being (only) a military implement for the British, ceased its activity when socket bayonets took its place. Following the same reasoning it is improbable that the example in discussion was brought by the Brits to Portugal as those massive downloads of weapons took place at a much later stage, with a heavy accent in the early 19th centuries for the Peninsular War, when the use of these things in Britain was long gone.
Also agreed that, the plug bayonet followed a more continued path in Spain, having become a traditional resource for hunting muzzle loading escopetas and, as well recorded, later becoming a decoration and ceremonial device; or even to complement the attire of uniforms, like those of Royal Estate gamekeepers we see caring for King Alfonso III (Plug Bayonet page 143), by the time shot guns had no need for bayonet emergency support. But i would not regard the specimen in discussion as being a ceremonial adornment; those were more worked up and decorated and less weapon looking, as we may see several around from Toledo output.
So the riddle remains; a ferrule of Germanic invention, a blade popular for the British and a hilt that nothing prevents to be Spanish ... or Portuguese; like this other example from my tiny collection.
So, in absence of inequivocal evidence, i (sentimentaly) elect it as a setup of Portuguese initiative ... if you don't mind, of course
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