[adrian]

I hesitate to use the term Cutlasses ...because that term never really caught on until very lately.
During this period the term 'cutlass' was absolutely the description used.

I was surprised to see that these weapons werent issued to Royal Marines who were issued with those incredibly long bayonets ...

That web based article is misleading and neglects to explain that the P/1859 Cutlass was fitted to the P/1858 Naval Short Rifle, it was not for the Pattern 1853 Enfield Rifle, as that article claims, nor does it even fit to that arm. In the late 1850s the Royal Marines were armed with the Altered Pattern 1842 Rifled Musket and transitioning to the Pattern 1853 Enfield Rifle, both arms had 39-inch-long barrels which employed a regular socket bayonet with a 17-inch blade (ref: British Ordnance Muskets of the 1830s & 1840s) followed by the Snider with the same bayonet. I am confused by your description of 'incredibly long bayonets'..... the RMLI did not have a longer bayonet than that issued to regular infantry.

I would recommend applying caution when relying upon web-based articles as so often, but not always, there are, at best misleading and at worst erroneous, 'facts' contained within, making it difficult therefore to discern fact from fiction.