The Peninsula, of course, is the San Francisco peninsula, which includes San Mateo County. SP commuter trains continued south of the peninsula to San Jose and other communities in Santa Clara County. This flyer lists fares; the Streamliner Memories reader who scanned it didn’t send a scan of the back, so I presume it was blank.
Click image to download a 325-KB PDF of this flyer.
The flyer has no other information, but fortunately someone has written that these fares went into effect in October, 1950. Someone else has written that fares on peninsula commuter trains didn’t change from August 1920 to October 1946, a remarkable record considering those tumultuous years. This may have been due to the California Public Utilities Commission discouraging SP from increasing its in-state fares during that time.
We’ve seen the fares during that time period in a 1943 timetable for peninsula trains. In that timetable, fares from San Francisco started at 22¢ to South San Francisco and rose as high as $1.14 to Los Gatos. In this flyer, fares went up to 25¢ to South San Francisco and $1.30 to Los Gatos, a 14 percent increase. As there was about 23 percent inflation between 1946 and 1950, this was a modest increase.