Vohenstraub is another one of the smaller Bavarian porcelain makers that not a lot of information is available on. The 26 refers to the pattern or shape number, more than likely the pattern number.
Bavarian porcelain is regarded as amongst some of the finest in the world. For example, a good set of Nymphenburg porcelain (Manufacturers for the Bavrian Royal Family) can go for as much as $35,000 to $40,000 Australian Dollars and is indicated by the Bavarian Coat of Arms as a mark.
As a general rule of thumb, if it says "GERMANY" then it was manufactured between 1894 and 1921. Post 1921, it should read "MADE IN GERMANY" althought this is the general rule, it is not 100 percent accurate.