Hi Guys,
Just for completeness sake:
Here are some examples of the pictured Maxim silencer. Since there was a good relationship between Maxim and DWM, it's not surprising to find them mounted on Parabellums.
The following images appeared in the 1912 edition of a German magazine 'Schuss und Waffe'. The article discusses the military possibilities of silencers on rifles. Conclusion was that it would take many, many years before silencers would find it's way into military service.