Although M. Genz prepared the listing mindful of the FIRST NAME needs of new parents, many of them are known to be SURNAMES going back hundreds of years.  Use Google to find the latest DGVBm.pdf or WB_Wo_18.pdf or ???.pdf with the 270,000 names.  Those applicable to our CyriacFamilyHistoryProject are already included amongst the couple thousand posibilities we've identified, so far.
genz 270.000 vornamen für buben

Ben Ciriacks' best guess translation (with online help) is:
 
The following 460 pages have 270,000 male first names, representing one of the largest and most comprehensive collections of this kind available to expectant fathers in the search for an appropriate name for newborn sons. Needless to say, the preparation of this book was a tremendous undertaking. After nine months when push comes to shove, there will still be two opinions for each name. For the money (it's FREE), parents can be assured that almost all possible names are represented here.
 
It was a joy and inspiration searching for these names.
 
M. Genz
 
As a compilation of international names, the authority for a specific name in each country is not guaranteed; i.e., the mere fact that a name appears here does not guarantee its validity.