In article <50fada$cp8@wiscnews.wiscnet.net>, galta@gbms01.uwgb.edu says...

>Can anyone tell me at what point Nikon ceased putting forked prongs on
>their lenses for compatability with earlier cameras, especially the Fs
>and F2s? Is there any designation by which one can tell if a lens (as
>advertised in a classified section like
>rec.photo.equipment.marketplace) does or does not sport a prong?

All non-AI, AI, and AIS Nikkors (except the current [plastic]
50mm f1.8 AIS, a [rare] earlier compact metal 50mm f1.8 AIS,
super-wides that required the mirror to be up when mounted,
and lenses slower than f5.6) have the prong.
E, P, and AF Nikkors (except the two made for the F3AF) do not,
though they can be used on early bodies in stop-down metering mode.
Hope This Helps